Restore System Settings in Windows Vista
Click the Start button, or the big Windows icon in the Start bar.
In the Start Search box, type systempropertiesprotection
If you are prompted for a password or for confirmation, type in your password, or click Allow.
In the System Properties dialog box, on the System Protection tab, click System Restore.
In the System Restore dialog box select Choose a different restore point, and then click Next.
Select the restore point that you want to use, which should be the one you saved as "PreZuneModification," and then click Next.
Confirm your restore point, and then click Finish
System restore restores the selected Windows Vista configuration and then restarts the computer.
Log on to the computer. When the System Restore confirmation page appears, click OK..