My comp is soo F**d up that I had switched from XP to Ubuntu to Vista. I mostly used cracked/nulled softwares and primarily use Photoshop and the likes.. so Ubuntu didn't last for long, although I love the interface of it.
Run a fileserver/media center with ubuntu so that I can stream across my apartment and when I'm feeling generous let my neighbors watch some shows I have on it. Work/Play rig is Windows 7 3 26" monitors
I'm currently using Windows 7 Home Premium, though soon I'll be converting to a Mac with OSX Lion. I'll probably still use Windows 7 in a virtual machine/Parallels to use Windows apps that aren't native to OSX.