Click Start, Programs, Accessories then System tools in Vista to open a folder with many helpful utilities to keep your PC healthy. Some of these are similar to those in Windows XP, but with subtle differences and improvements. Take the Disk Defragmenter tool, for example, which can be set to run according to a schedule. Select Disk Defragmenter from the list, and you should find that Windows has already set up a schedule with a tick next to where it says 'Run on a schedule (recommended)' . If not, tick the box and click on the 'Modify schedule' button to set how often you'd like the disk to be defragmented.