What makes you think that? Win7 uses fewer system resources than XP.
Win8 will be out in a couple of weeks. Unless you need a new PC in the next two weeks, I'd wait.
>The laptop is not powerful enough. Once I buy a new one, I will have Windows 7 Ultimate 64 bits allowing the installation of VS 2012.
Craig Berntson
MCSD, Microsoft .Net MVP, Grape City Community Influencer