To set or to change a screen saver in windows Xp follow the following instructions:
Just right-click anywhere in the desktop and click properties.
The display properties dialog box will appear.
In the display properties dialog box go to the Screen Saver tab.
Under the screen saver label, select the screen saver from the drop down list. If you do not want a screen saver, you can select none.
In the” wait” label you can also specify the idle time after which the screen saver should appear.
You can also check the “On resume password protect” check box for the computer to ask for the password when your screen saver is disturbed.
Now click on to the apply button.