When running dual core you may have to turn one of the cores off. The game has a problem specifically with the AMD X2. The procedure to turn one core off when running the game can be found in the SWBF2 Tweakguide. It also has other CTD issues. It sometimes refers to the SWBF1 tweakguide, but that's because the engines are similar.
SWBF2 Tweakguide HERE