Wow, I haven't heard of Battlefront 2 since like 2006, and back then my PC was a bit dated and had some trouble with the game. Do people still play it online? I may have to check it out, now with my more modern PC.
I would suggest:
DoW2- $5 over but close enough.
TF2
Warcraft 3
Day of Defeat: Source
Starcraft
IL-2 1946
Battlefield 2
Battlefield 1942- I should note that I can't get it to work on my machine anymore so YMMV.
DoW2, DoD:S, and Starcraft is pretty much all I play now, and before that it was CS:S, DoD:S, and Starcraft.