As for the windows advisory, you really do need to make a clean install if you're going to upgrade to a 64 bit Windows 7 from a 32 bit one (even if it's the same OS). There's no workaround. You don't really need to reformat, though. It just means it's going to install on top of your existing OS and you'll have to reinstall all of your programs/redo all of your customizations because all the registry entries will be wiped out (everything in your Windows folder will be moved to another folder named something like Windows.OLD or Windows.000, which you can delete if you're short on space)
