Get xp pro. the home version is the same as the pro version, the only difference being some networking stuff has been removed, and I think xp pro supports dual processors, while home does not.
for games, they are the same. I play games on pro at home, such as Unreal2, morrowind, CS, and AOM. At work I have played games on XP corporate, which is a version of XP pro that doesnt need activation. they all run games fine.