If it crashes while playing, your experiencing the same issue that a million other people are unfortunately. I don't have an answer for random CTD's, other than the 4gb patch.
Yep pretty much this. This game has a serious CTD issue right now that no one fix has been able to completely stop. Even with the 4gb patch I still CTD randomly every 1-4 hours. Also, be prepared to be ridiculed, insulted, and thread locked by rabid [censored] who will tell you the problem is with you and your computer, and not in any way tied to buggy, untested software from bethesda. Oh, and also be ready to hear "I'm playing fine for 147847230 hours so you are the only human with a problem new player, why don't you just quit and get off our forums."