I was in the store, checking out the games out of curiosity (I was buying something else) and realized there are a lot of FPS out there, and all I've played was Enemy Territory (the free one from a while back, not the Quake Wars). I liked Enemy Territory a lot, maybe because it was free, but I'm a little out of the loop on current FPS affairs. I've never played Half-Life, CS, Medal of Honor, Call of Duty, ET:Quake Wars, or pretty much anything else. Well, I have played the original HL a long time ago, but I don't remember much about it.
So, based on multiplayer aspects, what FPS would people recommend? I'm more interested in goal-oriented team-based objectives and as few douchebag players as possible.