Vonage

please help, I have no screensaver or background tabs

my pc not starts some games and come out from the game window and not starts the game. but in other pc that game runs well.

Recently i bought a used Dell pc optiplex280 and a sticker of XP CD key came with that When i installed XP from a pirated CD and gave that key, i proved to be invalid Why is so? I thought it may be a problem when activating but not on giving key........ Anybody can tell me my rights about that...