I have very lil computer knowledge, but im learnin...
Clicc start - find "control panel" and open it. Find "display" - the icon should look like a monitor. open that. Thatz where you configure your baccground and screensaverz and settingz. Clicc "settings" - It should be right there.
Or if ya have a "my computer" icon on your desktop you can open that and find your "control panel" there.
good luc