XP is so much better. Vista still has a lot of things to work out and isn't that impressive at all. There's a program you could download for xp to make it look like vista. So really, vista isn't really worth it.
I still use the Windows XP at the moment.
It is easy to install and reinstall the software.
I have never tried the the Windows Vista before.
I think the computer CPU more than 3.00 Ghz is available for Windows Vista.