I have vista 64 on my C drive and my games on my D drive. I know that when I install W7 on a clean C drive, it will not recognize the games on my D drive so I need to reinstall all of my games again. But if I try to install my games again over the old games will they install faster and write the details into the W7 registry or is it better to just wipe the D drive and install the games new again? Thanks.
Probably not, normally you could try a repair, but becuase there is nothing in the 7 registry to say that game is installed, then i would say no. You could install it to the same directory, but it would just overwrite the files, not just update the registry.
An alternative is to install W7 on C, backup your games on D drive (rename the folder containing them) then reinstall the games into the same original spot on D drive then overwrite with your old game folders. That way the updates games should be applied in most cases and any saved games etc that reside inside the game folders will be retained.