And while technically this is still "violent", the new Star Wars: Battlefront is pretty clean. What I mean by that is, while there is still a bunch of shooting, it is with laser guns and no bloody wounds, so it is fairly tame. Even many of the grenades are EMP-type explosives.

I'm pretty careful about the types of games I play around my 5-year-old son (he likes the Roller Coaster Tycoon series as well as Rise of Nations), but he is allowed to watch me play SW: Battlefront. I just tell him that the guys are getting stunned!

EDIT: Have you looked into Deus Ex 2 yet?