Hethu's Techno Babble

Mounting ISO disk images on a Virtual CD drive

2007-11-23T11:29:00.000+05:30

There is no built-in way in Windows XP to mount CD images (ISO, UDF, etc.). But a little known tool from Microsoft does this for you and it's free.

It's not the greatest CD mounting tool and does not have a sleek looking UI, but does its job pretty well.

It's an amazingly small download (59K) and is free from bloat. Download the Windows XP Virtual CD Control Panel from Microsoft. The Readme file tells you what you need to do.

How to add a shortcut to SendTo menu

2007-09-13T11:06:00.000+05:30

One of the first things I do on a fresh Windows install is to add Notepad to the SendTo context menu. As a developer, it is sometimes convenient to open a code file, XML file or a config file quickly in Notepad for quick edits without opening it up on Visual Studio or launching its associated program.

So how do you add Notepad (or any other shortcut, for that matter) to the SendTo context menu?

In Windows XP, by default, the SendTo shortcuts are saved in C:\Documents and Settings\[UserID]\SendTo folder. But this folder is hidden by default, so it was a pain to access this folder if you have Do not show hidden files and folders option set in Explorer Folder Options.

In Windows Vista accessing this folder is a much bigger pain. Now this SendTo folder is located at C:\Users\[UserID]\AppData\Roaming\Microsoft\Windows\SendTo\

But wait, you don't need to use Explorer to navigate to this folder. There's a much easier way in both XP and Vista!

In XP's Run menu or in Vista's Search menu (hey, I luuv this Vista search!), just type shell:sendto and hit enter to open the SendTo folder.

Simple. How simpler can it get?

How to repair your broken Windows

2006-09-27T14:19:00.000+05:30

No, this post is not about repairing your house windows.

Just the other day I found that some of the Windows command line utilities fails with an error "The NTVDM CPU has encountered an illegal operation".

Something has gone wrong and some Windows files have got corrupted. Not all command line tools generates this error, only some of them. So how do I fix this? Reinstall Windows? That seemed like a bit too extreme under the circumstances.

As it turns out, there is a built-in tool to check for corrupted system files and to automatically restore them from the original Windows CD. The tool is called, quite appropriately, "System File Checker" (SFC).

SFC runs the “Windows File Protection” and restores incorrect versions of protected system files with correct Microsoft versions.

You can run it from a command prompt as
SFC /SCANNOW

Make sure to have your original Windows CD around if any corrupted files needs to be restored.

Windows Genuine Advantage Notification

2006-06-16T10:09:00.000+05:30

Windows Update and Automatic Updates would install an update called Windows Genuine Advantage (WGA) Notification in Windows XP based systems.

After this WGA update, the next time you try to login to Windows, and if you happen to be running a non-genuine version of Windows you'd be greeted with this screen:

WGA Notification at logon

A notification Area balloon will remind you every so often to get a Genuine Copy of Windows, like this:

WGA notification balloon

It doesn't stop there. You'll also see a banner locked onto the desktop until you decide to get a genuine copy.

WGA desktop banner

This sure is a good way to irritate and even embarrass users who have installed pirated Windows XP on their computers.

From the first time users get this notification, they have 14 days to comply. After 14 days they will not be able to download software upgrades such as IE7 and Windows Defender. Critical security updates will still be available like it is now.

Microsoft hopes that by notifying users that they are not eligible for all Windows upgrades, it will drive more users to purchase a legal copy of Windows, and also report the counterfeit dealers that sold them their copy. In some cases Microsoft will give a free license to users who are victims of a high quality counterfeiting.

More on this on Microsoft Website.

The future of Windows UIs

2006-05-29T13:59:00.000+05:30

The latest range of upcoming Microsoft products have given up the conventional "standard" window elements like the menu bar and the toolbar. These are replaced with application specific UI items giving a whole new meaning to menus and toolbars.

Back in our computer studies courses, we were told to make the UIs look consistent, intuitive and "learn-once-and-apply-it-anywhere", and most of the apps today conform to these guidelines. But these theories no longer hold true for the upcoming Microsoft apps.

Have a look at Windows Media Player 11:

Windows Media Player 11

What you have is a border-less UI with a fancy skin you have to figure out. What used to be the blue “Title Bar” of a window is nowhere to be seen, and what looks like a skinned version of it now also shows the song play duration and length!

The 'standard' menus and toolbars are gone. This is replaced with what looks like a tab-pane which has buttons that light up and sub menus of their own when you click the small arrow beneath them.

Windows Media Player 11 with context menu

You still can access the main menu by right-clicking on the title bar, and even turn on the menu you used to have which is now called the “Classic Menu. But once you do, it totally ruins the skinned look.

Now have a look at Windows Live Messenger 8:

Windows Live Messenger 8

No menus and toolbars here either. If you try to access the main menu by right clicking on the title bar, it won’t work here. You got to click the new icon in the title bar (right before the minimize icon) for this. It takes 3 seconds to figure this out, but now you have two Microsoft apps that behave differently and look different.

And now the Microsoft Internet Explorer 7:

Internet Explorer 7

No menu, and umm… the toolbar is not a toolbar but a bunch of buttons scattered all over the place. And how do you get the menu? Right click on the title bar? Won't work. Is there a tiny icon before the minimize button? Not there. Ok, right-click on the empty tab space. Ah, there you have it - the option to enable the 'Classic Menu'.

Now you have three Microsoft apps that behave differently and look different.

Have a look at Windows Defender:

Windows Defender (formally Microsoft Anti-spyware) now runs behind the screens to protect against spyware. It's free!

Windows Defender

There is simply no main menu in Windows Defender and everything is controlled by the couple of buttons in the tool bar. The "Tools" button is no longer the Tools menu, but a button that changes the UI to show the "tools" available.

How is that? Now you have four Microsoft apps that behave differently and look completely different.

Now the upcoming Microsoft Office 2007:

Word 2007

Great... a whole new UI. What looks like a toolbar/menu bar/tab pane combination, with buttons of all sizes and icons of all sizes, some with text and some without, is the ultimate UI change to follow. This whole new combined UI thing clearly deserves a new name...and the new name given is – Ribbon!

The Ribbon will come in all the Office applications, dynamically changing the buttons and tabs to show what is relevant to do your current task.

Excel 2007 in a black theme

Office 2007 - New mail

What used to be the Tile Bar now has a big office icon on the left, called the "Office Button", which acts something like the old File menu. As you can see, most common buttons like the save and undo are stashed right on the "Title bar" – or what is left of it.

Office Button in Office 2007 applications

To conclude, now you have at least five Microsoft apps that behave differently and look completely different.

Where are we heading? When Windows Vista time comes, most Windows applications would be having their own UI implementations and behavior -- and that is going to be the end of consistent UIs. Stay tuned.

PS: Quick Tip: To quickly show the standard menu bar in all of these apps, you can simply hold down the Alt key!

IE7 Preview

2006-02-09T13:18:00.000+06:00

I've been using IE7 Preview for the past week and it's been great! Some of the first things you'll notice is the sleek new UI, integrated search providers, tabbed browsing (yes, everybody asked for it), a cool new Quick Tabs preview pane, a new Favorites Center, RSS feeds, bi-cubic zooming, a new print preview and of course the Phishing Filter!

IE7 Quick Tabs

IE7 Favorites Center

One of the first things I found strange is that text on IE7 was sort of
blurred than before. It turns out that this is because IE7 enables ClearType by default. This is a bad default, since most of us are not using LCD monitors, but you can quickly turn this off by going to Tools->Options->Advanced and clearing the 'Use ClearType' from the Multimedia section.

Another surprise you'll see is that if you go to google.com or yahoo.com for the first time, the sites will be providing a dialog to add them as an OpenSearch search provider for IE7.

Surprisingly Google is the default search provider in IE7 out of the box when I installed it. (?) Even then, this is what I got when I first visited Google.

I do get a lot of spam, and my Outlook 2003 spam filter does a decent job of catching 99% of them. But occasionally one or two of them slip into my inbox and today I got one of those famous Citibank phishing emails in my inbox. I don't click on links in such emails, but wanting to try out the new phishing filter in IE7, I went ahead.

Phishing Filter in Action (click to enlarge)

Cool!... IE7 correctly identified the site as a phishing site. Thumbs up! If you want to try this out, click this phishing link!

Finally, the Feeds feature gives you easy access to view and add your favorite RSS feeds. See how it shows my blog feed.

Battle for the platforms

2005-11-04T10:02:00.000+06:00

Recently Bill Gates has announced that Microsoft is planning on Internet versions of Windows and Office. I'm not sure what exacly this means or how they're going to pull this off, but it's quite surprising that Microsoft having their core products relying on the desktop for Windows and Office now moving on to platform independent web versions.

Yes, it's still vaporware, but a beta site is already up for Windows Live! and it's non other than live.com !

So what is Windows Live? Well, seems like it's a platform that brings together all your desktop application functionality to a browser. Starting off with Windows Live Mail, Windows Live Messenger, Windows Live Safety, Windows Live Favorites and Windows Live - what not. You can try these betas now.

Windows Live Mail is the next generation of Hotmail which was earlier announced with the codename Hotmail Kahuna. It promises the interface of the desktop version of Office Outlook 2003, with multi-select drag drop and right click context menus all with AJAX (Asynchronous JavaScript and XML) technologies. Watch out GMail!

While Microsoft is moving onto the web arena, the web frontier Google is moving onto the desktop space. Google released Google Desktop 2 recently, which is a combination of Google Desktop Search and the Google Sidebar all in one. So you get to see your GMail, your News etc all in one place plus the desktop search built on top of it.

As I have blogged earlier in March, Microsoft introduced their online (RSS) news reader at start.com with cool drag and drop and AJAX tricks. Google recently joined the game with their own Google Reader. Check that out. It's still beta like every other Google thing, but still very impressive. Btw. when is GMail coming out of Beta? It's been in beta stage since...... forever. :-/

Side-effects of "con" Console

2005-10-18T13:54:00.000+06:00

Few days back I got an email which read:

An Indian discovered that nobody can create a folder anywhere named as "con"

This is something pretty cool... and unbelievable... At Microsoft the whole Team, including Bill Gates, couldn't answer why this happened!

Try it out yourself...

Anyone who is old enough to have used DOS would know better. What a lame and ignorant thing to say that even Microsoft couldn't answer!

I was even more surprised to hear the same lame story on Yes FM Radio today. The show host has obviously got the same email and thought it was cool enough to share on air and went on saying "can you believe it, even Bill Gates doesn't seem to know why"!!!

Geeeez... talk about being clueless and ignorant!

Let me give you a clue. Almost everyone with a DOS background (I know, I'm one of those few l337s :) knows that "con" is the named IO device for the primary console.

So if you want to copy the output of a file to the console, you can type at a Command Prompt:
copy file.txt con

And if you want to create a new file with the contents you enter at the console, type:
copy con file.txt
key in your text content, type Ctrl-Z (or F6) and hit Enter to save the file.

This is one of my favorite ways to quickly create DOS batch files, and I've been doing this for years!

Now, getting back to the original email about not being able to create a folder named "con"; answer this: if you can create such a folder, what on earth would happen to my favorite copy con file.txt command?

And oh, while we are at it, "prn" is also such an IO device (for local printer) and you can't create such a named folder either, and I am quite sure Microsoft (and Bill Gates) are quite aware of this unbelievable thing too!

This reminds me, another one of my DOS-days favorite is to use copy con prn and use the locally attached printer as a typewriter. ie. type something on the console and hit Enter to print that line on the printer. Amuse yourself with good ol' DOS tricks!

Me @ Microsoft Tech.Ed 2005

2005-10-18T10:13:00.000+06:00

I finally went for the much awaited Tech.Ed 2005 show held at Waters Edge, Battaramulla, Sri Lanka.

The event started off with a cool thabla and drums musical show with flashy lighting effects and high tech sounds. For a moment, I was stunned and was wondering whether I came in for the right techie event! :)

After the intro, and after some keynote speakers, it was straight down to techie sessions.

There were four parallel sessions going on at one given time; so you got to choose among them and decide which sessions you are most interested in. As a developer and enthusiast in Microsoft technologies, that became quite a difficult choice for me. For example, I had choices like Visual Studio 2005 Team System, Windows Mobile, SQL Server 2005 and Windows Vista sessions. You go for one, you miss three others!

This was the first time we had such an event in Sri Lanka, and yes, there were some minor glitches especially due to bad coordination and time management in some sessions. At one time, one session went on longer than it was scheduled, and once it was over, the people in that session could not attend the other sessions from the beginning since those were already started on schedule. The organizers should have better coordinated this. Maybe we'd do better next year.

Overall, it was a great event with loads of techie sessions and fun!

Thats me near the XBox gaming zone.
The last day night was a fun night with loads of Microsoft giveaways, hot dancing and booze! :)

Yea, Microsoft style fun!

Random text in Microsoft Word documents

2005-10-07T11:03:00.000+06:00

You have obviously heard before that you can type =rand() and hit <enter> in a Word document to auto insert paragraphs with the text: "The quick brown fox jumps over the lazy dog".

What is interesting is that this is not a hidden Easter egg. It is a known documented feature, and is described in a Microsoft Knowledge Base article.

Basically, the idea is to quickly add some sample text to a document. Perhaps to test the print margins, the header/footer behavior or to see how the text looks like when you apply the new Style you just created.

I found this really handy when I wanted to test the Booklet printing features in Word and wanted at least 5 pages of text. :)

Now you don't have to blindly type


asdf<enter>
fdsaa<enter>
ds<enter>
dsfdsfs<enter>

repeatedly to fill in a document.

Use =rand(p, s) and <enter> to insert p number of paragraphs with s number of sentences.

So, =rand(3,5) would insert 3 paragraphs with each having 5 sentences of "The quick brown fox jumps over the lazy dog".

Go ahead, try something like =rand(100,100)

(note that the maximum number you can give for a parameter is 200)

Microsoft Tech.Ed 2005 in Sri Lanka

2005-09-14T11:55:00.000+06:00

Finally!

Microsoft is doing something serious here for us in Sri Lanka. The Tech.Ed 2005 Sri Lanka will be held in October 2005.

Yes, it's going to be BIG! And you can bet, I'll be there!

Playing the Game: Half-Life 2

2005-09-01T11:14:00.000+06:00

These days, my late nights are exclusively spent fighting my way through the amazing first-person shooting game - Half-Life 2.

The graphics, AI and surround sound are amazing, giving the best realism ever. Especially the physics of the game environment is unbelievable. Try hitting a wall, a metal post or a wood plank and they all will sound and feel as in the real world. Kick something into the water and it will float depending on its physical properties. The physics engine handles the rules of mass, friction, gravity, and buoyancy amazingly well.

What’s more, even Microsoft is interested in Half Life 2.

Minimize to Tray (Notification Area) and show Balloon Notifications in C#

2005-08-29T14:00:00.000+06:00

I have been searching the web for quite a while for a .NET class that can do the minimize to tray animation and show balloon notifications in the notification area.

It is quite easy to make an .NET application show a notification icon in the taskbar notification area with the built in NotifyIcon .NET control. But it is not possible to show a balloon notification message like the one you see when you plug in a USB device, or the one that reminds you of "Files waiting to be written to CD". Also, the built-in NotifyIcon control doesn't allow you to do the window minimize animation onto the notify icon area as it should. Why have Microsoft not exposed these Win32 functionality to the .NET 1.1 control?

(By the way, there is no such thing called the System Tray, it is officially called the Taskbar Notification Area, but most people still call it the Tray)

If you want to do a minimize to tray, your best bet is to set Form.ShowInTaskbar=false; and show the NotifyIcon. But this results in an ugly and a bad minimize animation. The window appears to minimize to the taskbar area and disappears into thin air, and then suddenly the icon appears in the notification area out of the blue. That isn't right.

There are several CodeProject articles giving ways to do this properly. But the best implementation I have found yet is by Matt Griffith in his .NET utilities class library. His NotifyIcon class can do the following:

Show the notification area icon and tooltip
Minimize to Tray with window animation
Restore from Tray with window animation
Show balloon notifications in the notification area (cool!) until a given timeout

The class library is very well documented. Unfortunately no code samples are given but it's quite easy to figure it out.

Dotted GMails

2005-08-23T11:08:00.000+06:00

So it seems that GMail addresses can have arbitrary dots in the first part of the email address, and still all the mails sent to those addresses will land on your mailbox properly.

So for example, all mail sent to hethu.n@gmail.com or h.e.t.h.u.n@gmail.com or he..th..un@gmail.com or whatever the creative dot combination you can come up with is still yours and all the mails will come to the same account.

Now why would this be useful? Well, you might want to give a specific dotted email address freely to the spammers and catch the spam easily with a mail filter and trash them. So when you are registering for a new website next time with your GMail address, think of giving it a dotted email address.

But wait, don’t get too exited. Will this neat cool feature create more problems than it solves? Couldn't the spammers just create arbitrary dotted addresses and spam you even more? After all, now they have thousands of dotted email aliases instead of one to spam you on!

Accessing ADO Constants from ASP pages

2005-05-17T10:57:00.000+06:00

Here's a tip for old ASP coders. (this is not for the new ASP.NET)

When using ADO in ASP pages, it is convenient to use the various ADO enumerated constants (eg. adOpenKeyset, adLockReadOnly, etc.) instead of the obscure numeric values that can be used as an alternative. But the only problem with this on ASP pages is that the adovbs.inc file, which declares these constants, must be included with the each ASP page that uses the constants.

While this gives more readable code, it increases the size of the ASP pages and adds overhead when the ASP page is compiled and run when it is called.

If you don't like the idea of including the adovbs.inc file in your ASP pages because of the related overhead that is incurred, but you would like the convenience of not having to use meaningless constants in your code, the option is to load the adovbs.inc file using a <METADATA> tag instead of adding it as an include, using this format:

To make life even easier, you can have this line in the global.asa file instead of adding it on all the ASP pages. More information on MSDN.

10 Immutable Laws of Security

2005-04-21T12:28:00.000+06:00

I was browsing the MSDN Blogs and come across this interesting post in the IEBlog about SSL and TLS security. Digging through, I ended up with this quite informative Microsoft TechNet article.

The 10 Immutable Laws of Security:

Law #1: If a bad guy can persuade you to run his program on your computer, it's not your computer anymore

Law #2: If a bad guy can alter the operating system on your computer, it's not your computer anymore

Law #3: If a bad guy has unrestricted physical access to your computer, it's not your computer anymore

Law #4: If you allow a bad guy to upload programs to your website, it's not your website any more

Law #5: Weak passwords trump strong security

Law #6: A computer is only as secure as the administrator is trustworthy

Law #7: Encrypted data is only as secure as the decryption key

Law #8: An out of date virus scanner is only marginally better than no virus scanner at all

Law #9: Absolute anonymity isn't practical, in real life or on the Web

Law #10: Technology is not a panacea

I highly recommend you read this 10 Immutable Laws of Security at Microsoft TechNet.

The Geek Wedding

2005-04-15T09:37:00.000+06:00

Nothing geeky about it, really.

My wedding went on as any conventional Sri Lankan Sinhalese wedding. My wife Chãndima wore Kandyan for the wedding on 28th March 2005 and an Indian saree for the home-coming ceremony, on the 2nd of April 2005.

Check out more wedding photos as a slideshow in my MSN Space.

Amazing picture

2005-03-22T11:23:00.000+06:00

Just the other day I received an email which read:

Amazing picutre! Juz press CTRL+A and you will know why is it so!

Online RSS news reader

2005-03-17T15:43:00.000+06:00

I was reading through MSDN blogs and came across a not-yet-public online news reader from Microsoft. It still goes as an MSN incubation project but still, works great.

The online news aggregator is quick, neat and fast with DHTML (think GMail) and I've really gotten to like it. Although it has some quirks and lacks customization as I would like it to have, it gathers news from XML and RSS feeds pretty well and is very easy to use. Added bonus: MSN Search is integrated.

So, if you want to add my Blog to your news feed (where I post very very rarely now!), here's the link. :)

http://www.hethu.com/blog/atom.xml

And you can also use the orange "xml" image link at the very botom of the page!

GMail invitations give away

2005-01-17T15:31:00.000+06:00

I know, almost everyone has GMail accounts by now, but its surprising that still some GMail invites are sold at $10 or more on eBay.

Well, if you are interested in a free 1GB Google mail account, I have plenty to give away - for Free! :)

Just drop me an email.

Microsoft Certified

2004-12-31T17:00:00.000+06:00

I am a Microsoft Certified Solutions Developer (MCSD). Now I can proudly use any of these logos in my CV :-)

When comparing the MCAD to the MCSD Credential based on the Software development life cycle, it comes to something like this:

Here is the list of exams I went through to get the MCSD credential.
(I have no idea why there is a huge space below, seems like a Blogger stylesheet bug)

Exam ID	Description	Date Completed
300	Analyzing Requirements and Defining Microsoft .NET Solution Architectures	Dec 17, 2004
320	Developing XML Web Services and Server Components with Microsoft Visual C# .NET and the Microsoft .NET Framework	Aug 18, 2004
229	Designing and Implementing Databases with Microsoft® SQL Server™ 2000 Enterprise Edition	Jun 29, 2004
316	Developing and Implementing Windows®-based Applications with Microsoft® Visual C#™ .NET and Microsoft® Visual Studio® .NET	May 26, 2004
315	Developing and Implementing Web Applications with Microsoft® Visual C#™ .NET and Microsoft® Visual Studio® .NET	Dec 18, 2003

Now, where do I want to go today?

Where the search begins... and ends

2004-12-15T10:01:00.000+06:00

Microsoft just launched its latest search tool - MSN Toobar Suite. It tries to unify the searching experience by searching the desktop files, emails and the Internet. The suit installs three toolbars; the clasic MSN Toolbar for IE, another for Outlook, and a one called the MSN Deskbar for the taskbar.

Even at its beta stage, it sure does a pretty good job. The initial indexing ran in the background for about 40 minutes without interrupting me or taking the system to a crawl. Once done, I fired my first search for "Windows media SDK". And within milliseconds, I was shown the results then and there. Pretty impressive. It was really really fast!

Wait, not too impressive when you see that it eats up a lot of your valuable taskbar space! And when you also have the Windows Media Player minimized, it comes to something like this:

About 50% of my taskbar already gone! Good thing is, you can drag it off the taskbar and stash it anywhere on the desktop or remove it altogether.

Now why did Microsoft give us a separate MSN toolbar search without integrating the new ultra-fast search engine to Windows Search itself?

Your own space in CyberSpace with MSN Spaces

2004-12-07T13:02:00.000+06:00

Microsoft is giving all the kids and the grandma's a space on the CyberSpace.

They call it MSN Spaces, a place where you can publish all your photos, have your own blog, have your music playlists directly linked to MSN Music, have your favorite links, keep your personal profile, and more... all in one place. Oh yea, think of it as a new alternative to a personal homepage, for every kid, nerd and dog out there.

The new MSN Messenger 7 will have direct access to your contacts' "Spaces". And yes, if you do not wish to make your Space public, you can even limit access to only the people on your MSN contact list.

It's still at its beta, and it has some nifty features using all the cool DHTML magic; with customizable themes, Web Parts, drag and drop layouting, your picture slideshows and whatnot!

Check it out: http://spaces.msn.com/members/hethu

Google math problem

2004-09-23T13:01:00.000+06:00

I saw this interesting news article about mysterious billboards showing a mathematical problem.

The billboard simply says:

{ the first 10-digit prime in consecutive digits of e }.com

and it's up to you to figure out the rest.

Now I'm not a mathematical genius to figure this out, but I was yet interested to find the answer anyways. The obvious and the easiest is to Google for it, and I ended up with this nicely written answer by Marcus Kazmierczak.

In case you are too lazy to visit that link, here's a brief explanation:
e is the base of the natural system of logarithms, having a numerical value of about 2.71828 (though the number goes on forever). Now the prime number that matches the billboard criteria is 7427466391. So following the billboard problem, once you visit 7427466391.com you end up with this:

Congratulations. You've made it to level 2. Go to www.Linux.org and enter Bobsyouruncle as the login and the answer to this equation as the password.

f(1)= 7182818284
f(2)= 8182845904
f(3)= 8747135266
f(4)= 7427466391
f(5)= __________

Woa... another math problem.

So what’s the reward when you figure this out? It turns out to be a marketting pitch to hire smart engineeres for the Google Labs. Google doing its tricks again!

Since you are at it, also check out this hilarious Google's Luna center jobs!

Show Desktop, Minimize All : the difference

2004-09-20T10:20:00.000+06:00

Have you ever wondered the difference between the two?

In XP, if you have the QuickLaunch toolbar enabled, you can easily do a Show Desktop by clicking the icon, or by right clicking on the Task Bar and selecting that option, or even easily by doing the keyboard shortcut: WindowsKey + D. (do it again and it will undo the Show Desktop)

You can also do a Minimize All; by using the keyboard shortcut WindwosKey + M. (undo it by using WindowsKey + Shift + M)

So what’s the difference?
Well as it turns out, there is a technical difference between the two operations.

Minimize All is pretty straightforward and does exactly that; it simply minimizes all the windows that has the Minimize icon (ie. windows supporting the minimize operation).

Show Desktop goes a bit further. First, it Minimizes all the windows, then it sets the Z-Order of the desktop to make it come to the front. Why? Because some modal dialogs and some special types of windows may not support the Minimize operation.

So in short, Minimize All simply asks all the open windows to Minimize themselves, while the Show Desktop does the same, plus makes sure that the desktop is not being obstructed by anything that doesn't want to listen to the minimize command.

Now you may wonder, why isn't the original window order always preserved when you undo a Show Desktop? Here's the answer from Raymond Chen of Microsoft:

When the windows are restored when you undo a Show Desktop, Explorer goes through and asks each window that it had minimized to restore itself. If each window is quick to respond, then the windows are restored and the order is preserved.

However, if there is a window that is slow to respond (or even hung), then it loses its chance and Explorer moves on to the next window in the list. That way, a hung window doesn't cause Explorer to hang.