Turn System Restore On or Off

Restore points are created automatically every day, and just before significant system events, such as the installation of a program or device driver. You can also create a restore point manually.

For automatic restore points to be created, System Restore must be on. It should already be on, but if not here's where you can turn it on:

1. Open System by clicking the Start button , clicking Control Panel, clicking System and Maintenance, and then clicking System.
2. In the left pane, click System Protection.  If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
3. To turn on System Protection for a hard disk, select the check box next to the disk, and then click OK.
   – or –
   To turn off System Protection for a hard disk, clear the check box next to the disk, and then click OK.
   Source: http://windows.microsoft.com/en-US/windows-vista/Turn-System-Restore-on-or-off