Out of the two choices you have listed, MW1. Especially if it for multiplayer. No admins is a bad thing.
Or you could get Medal of Honor: Tier 1
. I find the combat a lot more satisfying than BFBC2. Even in hardcore mode, BFBC2, takes more than 1 hit to kill someone with a sniper rifle....wth?
I personally like the conquest type gameplay the best as it's more in line with teh BF series, but BFBC2 is a joke comparatively. Not to mention, I get some seriously weird lag in the menu screens for no reason. Yet I get 90-140FPS in game (maxed).
At any rate, I think that MoH has as good graphics as BFBC2, the weapons are more realistic; meaning that it shouldn't take a full magazine to drop anyone --even if they are wearing body armor.
The weapon selection is nice. I, personally, had a good time playing the beta. When the price drops some, I'm definitely getting it.