Although I don't run XP Pro, from watching The Screen Savers and other fine programming on Tech TV, I've come to guess that Windows Policy Editor can probably do what you want..
Start -> Run -> "poledit"
*Don't include quotes...
:-\
BTW, what games? Most new games, when installing them, have an option wether to just allow the person installing the game to use it or everyone... try re-installing the game if its a newer one..
