What would make The Sims 2 keep crashing?

My vampire Sim, Vlad Dracula, bit a friend on the neck to turn him. As soon as the friend floats in the air and starts to turn, my game crashes. This happens every time I want to bite a Sim. I'm not sure if this will help, but I found some FAQS and cheats and turned this on: boolProp TestingCheatsEnabled true just to see what it was all about. Would this be causing my crashes? Also, I did boolProp TestingCheatsEnabled false to turn it off, but the commands on my mailbox are still there, and my game still crashes when I try and Vamp a Sim. I also have a lot of custom content, but my game has never crashed before. It only started crashing when I attempted to turn a Sim to the nightlife. Is there anyone who has experienced this or has any info that may help me?