This happened 3 times to me tonight. I would be playing the game the normally and then the game would just freeze. Everything locks up, including the sound (it keeps playing the same sound clip over and over). There was no way to fix it except to Ctrl+Alt+Del and end task. But even when I opened the Task manager, my mouse was still locked. I had to navigate the Task Manager with my keyboard to shut down BF2 (which was labeled "Not Responding"). My computer was fine after that, until it happened again and I had to go through the whole thing again.
The first time it happened, I was Canadian on Lebisey. I had grabbed a sniper rifle from main and was making my way towards the West AT flag. I was in the field to the north of the flag, about a grid away when it froze. The next Time it happened was on Totalize, an hour or two later. I had just spawned into the Canadian Airfield with an engineer kit when it froze. The third time was about 15 minutes after the second time, still on Totalize. I spawned at the Canadian airfield with the engineer kit, and hopped into a Typhoon. As I started to pull out from under the camo net, it froze again.
After the third time, I decided to take a break from FH2 and check the forums. I figured I should post this, to try to get to the bottom of it.