OK, maybe I've jumped the gun here. I thought you had used the System Restore to back up your files. When you go to System Properties, you can create a restore point anywhere, including an external hard drive.
But,
"System Restore helps you restore your computer's system files to an earlier point in time. It's a way to undo system changes to your computer without affecting your personal files, such as e‑mail, documents, or photos."
"System Restore is not intended for backing up personal files, so it cannot help you recover a personal file that has been deleted or damaged. You should regularly back up your personal files and important data using a backup program."
Did you use some other backup program?
Lastly, if you have a C:\Windows.old folder, then you may be in luck
The "Users" folder - most programs store a user's personal files in the "User" folder. Generally, you do not find personal files in the Windows folder or in the Program Files folder. The "Users" folder contains one folder for each user who logged on to the computer in Windows Vista. For example, the following folders appear in the "drive:\Windows.old\Users" folder:
drive:\Windows.old\Users\UserName\Contac…
drive:\Windows.old\Users\UserName\Deskto…
drive:\Windows.old\Users\UserName\Docume…
drive:\Windows.old\Users\UserName\Downlo…
drive:\Windows.old\Users\UserName\Favori…
drive:\Windows.old\Users\UserName\Links
drive:\Windows.old\Users\UserName\Music
drive:\Windows.old\Users\UserName\Pictur…
drive:\Windows.old\Users\UserName\Saved Games
drive:\Windows.old\Users\UserName\Search…
drive:\Windows.old\Users\UserName\Videos
If it exists, you should be able to get your old user files back (click
HERE for an example and
HERE for a tutorial).