Have you tried booting into Safe Mode, and running System Restore?
Start / All Programs / Accessories / System Tools / System Restore / Restore my computer to an earlier time / Next
Pick a date before the problem occured.How to start Windows in Safe Mode
This is a registry edit. If you're not comfortable with working in the registry, DO NOT ATTEMPT
Improper changes to the registry could render your computer inoperable.Remember to backup the registry before making any changes.
Instructions, on how to do that, can be found here:How to back up, edit, and restore the registry
Try this:kellys-kornerRestore Desktop Icons and Taskbar
, on the Right