You can do something very similar.
You can run the following file from Shell:
[Shell]
Command=2
IconFile=explorer.exe,3
[Taskbar]
Command=ToggleDesktop
The extension of such file is "SCF", for example, the name would be "Show Desktop.SCF". Just create a file and click it.
When you run such file, you can get pretty much what you want.
I'm sure you can do it programmatically. First, try to make and run this file and see if this is what you want.
If found the following C# sample:
http://blogs.msdn.com/b/robgruen/archive/2004/02/24/79294.aspx[
^].
—SA