If you’ve ever experienced random slowdowns and high CPU usage for no apparent reason, System Restore might be responsible for it. Believe it or not, System Restore can take up as much as 15% of your hard drive.

System Restore is a very useful feature that acts like a built-in time machine. The System Restore service creates snapshots of your system, so that you can always roll back if there are any unexpected problems.

But if you never use it and prefer other backup methods, like saving all your valuable data on an external hard disk or a DVD, it will be worth it to disable System Restore altogether.

If you have Windows XP:

1. Right-click My Computer and go to Properties. Alternatively press the Windows key + the Pause/Break key on your keyboard. That will take you straight to the System Properties dialog box.
2. In the System Properties dialog box, click the System Restore tab
3. 
4. Click the Turn off System Restore check box (or the Turn off System Restore on all drives check box).
5. Click OK and then confirm that you want to turn System Restore off.

If you are a Vista user:

1. Go to Start and select Control Panel
2. Select System and Maintenance and then go to Backup and Restore Center
3. Select Create a restore point or change settings
4. If UAC is active, click Continue
5. Select the System Protection tab
6. Uncheck your hard drives under Automatic restore points
7. Click Turn System Restore Off and then click OK

Remember that if you disable System Restore, all your previous restore points will be deleted. If you don’t want that to happen, leave this service enabled.