If Spy Software XP is visible you have to click on Uninstall shortcut
within Windows Start Menu:
Start > Programs > Spy Software XP > Uninstall
or find Spy Software XP uninstall record within Add/Remove Programs:
Start > Settings > Control Panel > Add/Remove Programs > Spy Software XP
If Spy Software XP is invisible you have to run Spy Software XP Control Center by pressing program hotkey (default hotkey is Ctrl+Alt+Shift+L). You will get following window then:

Click on File menu and choose Uninstall to uninstall program. You have to reboot computer to finish uninstall process. It's obligatory condition.