Use
System Restore to Undo Changes if Problems Occur
Windows XP Professional makes it easier to resolve
problems if they occur in your system. You can use System
Restore to remove any system changes that were made
since the last time you remember your computer working
correctly. System Restore does not affect your personal
data files (such as Microsoft Word documents, browsing
history, drawings, favorites, or e–mail) so you won’t
lose changes made to these files. Windows XP creates
“restore points” every day, as well as at the time of
significant system events (such as when an application
or driver is installed). You can also create and name
your own restore points at any time. Creating a restore
point can be useful any time you anticipate making changes
to your computer that are risky or might make your computer
unstable. If something goes wrong, you select a restore
point and Windows XP undoes any system changes made
since that time.
When you run System Restore, a calendar is displayed to help you find restore points. If you don't use your computer every day, some days might not have any restore points. If you use your computer frequently, you might have restore points almost every day, and some days might have several restore points.
To create a Restore Point

To view or to return to this restore point, from the Welcome to System Restore screen of the System Restore Wizard select Restore my computer to an earlier time. Then select the date when the restore point was created from the calendar in the Select a Restore Point screen. All of the restore points that were created on the selected date are listed by name in the list box to the right of the calendar.
To set advanced restore options