In response to Gargoyle's suggestion about partitioning the drive....you can do that, in fact Windows 7 has a tool that makes it really simple to accomplish...however, there is a flaw that Vista had, and for some reason is carried over to Windows 7, that if you partition your drive, and install an older version of windows, the system will NO LONGER recognise the newer version, and it is a right pain in the ass to fix.

I'm sorry, Joe, I didn't look carefully enough at that link....to see if it would work for your version.

I wouldn't be surprised however if some one found a way to get around that...