Upgrading to Windows 7
Depending on your hardware and your current edition of Windows Vista, you can use the Upgrade option during Windows 7 installation to upgrade from Windows Vista to a corresponding or higher edition of Windows 7.
Upgrading is the most convenient way to get Windows 7 on your computer, because it keeps your files, settings, and programs from Windows Vista in place.
Watch the clip for more details or visit this page on Microsoft’s Windows website.