It should be able to play battlefield and quite well at lower resolutions provided you have a good enough GPU with it. I hear that BF3 is designed to optimize 4 cores, but that doesn't mean that the 2100 shouldn't and wouldn't play the game well, it probably won't be as good as a the higher end quads but should play well nonetheless.
The 2100 with its HT should be sufficient enough to play any game well, provided all hardware is the similarly up to standard.