Operating System Upgrade

[NeciFiX]

Hi,

I bought Windows Vista Home Premium as an OEM, and was wondering, when and if I decide to buy Windows 7 Home Premium UPGRADE, would it upgrade normally? Meaning, if I bought Windows 7 Upgrade version instead of Full, would it work right? Would I have to do a clean install or would it just transfer all my files into Windows 7?

Thanks,

NeciFiX