My game used to do this. At the time I only had two custom content things- and they were downloaded sims. I finally just got mad and deleted the house. I recreated the family and low and behold this time the game didn't crash but the male sim would go out to his car when it was time to go to work and just stand there. He'd never leave the lot and then he'd get fired. No matter what job I got him... same thing would happen everytime. SO- the game wasn't crashing anymore but now the sims wouldn't go to work.
I deleted the custom sim and all his content and it seemed to fix the problem.
NOW- this could be a total fluke in my game and not help you in anyway but I thought I'd throw the idea of a "flawed" sim your way... just in case.
PS- now my game crashes everytime it snows. LOL
I had to set all my neighborhoods to a more tropical climate as I can't seem to figure out why this is happening either. GEESH.... :smt120
I hope whatever the "thing" is causing you troubles you find and fix it. (HUGS!)