Intalling Windows 7
Deployment Scenarios
Upgrade Computer (in-place upgrade)
You can upgrade from Windows Vista Service Pack 1 (SP1) to Windows 7 in place, which means you can install Windows 7 and retain your applications, files, and settings as they were in your previous version of Windows Vista. If you want to upgrade from Windows XP to Windows 7, however, you will need to use the Refresh Computer scenario, which preserves files and settings but not applications.