System restore will take up resoruces such as memory and hard-disk IO. Personally I have been using windows xp ever since it came out and I have never used system restore.  If you are going to disable the system restore make sure you backup important files to anther disk such as USB stick / CD-ROM / Tape drive and so on.

To disable system restore in windows xp do the following

1. Right-click ‘my computer’ and click properties

2. Click the “System Restore” tab at the top.

3. Check the box “Turn off system restore on all drives”