In general, drivers(like graphics, sound, printer,etc) for Vista works on Windows 7. HOWEVER, you may still run in to problems for things like printers, cameras,etc.

Will the full version of Windows 7 work on my Vista?

Windows 7 is no longer the current version, and there are scammers selling pirate copies, so caveat emptor. You will need to buy a version that is as good as or better than your current version of Vista. For example, you can upgrade from Vista Home Basic to Windows 7 Home Basic, Home Premium or Ultimate.

Can I use Vista drivers for Windows 7?

Your vista x64 drivers will work with Vista as Windows 7 is backwards compatible, I installed a copy yesterday and didn’t even need to download the drivers for my graphics card (Nvidia 8500gt).