Is that the only problem? Does everything else work OK? Do the desktop shortcut icons show and do they work?

If so, have you tried creating a new desktop wallpaper by opening a .jpg picture in one of your folders, RIGHT click on it, choose "Set as desktop background"?

And more importantly, because it appears like the Autoruns programs deleted a registry entry, have you tried running System Restore to a time before the problem occurred? (Right click "My Computer", choose "Properties", then "System Protection" tab, then the System Restore button. Follow the prompts to choose a restore date that is before the problem.

http://www.howtogeek.com/howto/windows-vista/using-windows-vista-system-restore/

Hope this helps.

Grif