Now only if there was a way to edit the Show desktop button into a Windows Button + M key.No. Nor is there a way to call teh Windows key with script.
Actually, that's false. Totally completely false and just plain untrue. There are a couple of options for this kind of thing although it will require some (perfectly free) utility to be installed.
WinKey is a small program that works with XP and Vista. It allows you to set any program or Windows action to any key combination you wish. Including the Windows key.
AutoHotKey is a Macro scripting tool that allows you to do just about anything you want from launching a program to building small script based applications and assign them to any key combination. Combatible with XP and Vista.
I HIGHLY recommend AutoHotKey as it will do what you want no matter what it is you want. It has a bit of a learning curve, but once you start using it, you won't want to get rid of it. I used WinKey from Windows 98SE through Windows XP until I found AutoHotKey and found it could do everything WinKey could do plus a WHOLE lot more.
You can Google for each of these utilities.