Using System Tools for Basic Maintenance
All Windows XP computers have at least one hard disk. The hard disk acts as your computer's storage area. Almost everything installed on your computer—applications, files, folders, and the operating system—is stored here.
With general use (creating new files, deleting files, or installing new software), your hard disk can become fragmented. This means parts of the same disk file become scattered over different areas of the disk. A fragmented hard disk slows down your computer and hinders its performance.
To keep your hard disk running smoothly, you must routinely defragment, or "defrag" the hard disk. The Disk Defragmenter tool can help you do this.
Note: You may need to be logged in as an administrator or as a member of the Administrators group to perform some tasks associated with the Disk Defragmenter. Disk Defragmenter should be run every three months.