I don't know, but I had very very bad experiences with Win2000, constant kernel errors,  user sessions that would get corrupt after a couple of uses, page file getting blocked, blue screens, weak login protocol that allowed script kids to gain admin passwords. A real mess, I preffer WinXP, which felt like a Win2k bugfix + eyecandy.

Now I don't think W7 is a bugfix of Vista, I think Vista was a Beta version of W7 :bored: