I was looking around on the internet when I came across this article :http://www.istartedsomething.com/20061029/royale-noir/
It adds 2 more colors to your boring XP themes. Black and the media center Blue. All you have to do is extract the files to your themes directory of you XP copy. It works because the theme were created by Microsoft and they have signatures. The black was created but never used. (probably because it aint to atactive)
well there you go I hope you enjoy it.