Sims 3 crashing in create a sim. and is it bad to delete user presets files?

[Cassie]

You need to run the game on windowed mode - this can get rid of crashes for a start, or make them less frequent at least, but that's not always true. However if it does freeze, you can close the game without having to restart your computer. I used to have the exact same problem, however I downloaded a free update for my graphics driver and I now have no crashes whatsoever. Dunno if that could help you. Worth a shot.

Seeing as you have no CC, I don't know what causes the game to crash in CAS but it's a common problem. There's nothing I can really say as I'm not totally tech-savvy except, try it in windowed mode and try downloading a free graphic driver update if you can.