So I have Vista Ultimate right now, which I was given through my college. I want to upgrade to Windows 7, but I don't need Professional or Ultimate. Home Premium would be just fine. Is there a way I can buy the 50 dollar upgrade to Home Premium or am I SOL because I have Vista Ultimate? If so, I still have my XP Professional installation discs, so would I be able to downgrade from Vista to XP Pro, then upgrade from XP pro to Windows 7 Home Premium?