It's odd because I haven't had any issues playing (at least in the 30 minutes I've played).

The only mods I'm running are the BT Mod, the Unofficial Oblivion Patch, and the Unofficial Shivering Isles Patch (I have SI and KotN from 5th Anniversary Edition). Patch 1.2.0416 (I think that's it) is installed.

Any help? I did install and reinstall the game twice before this install (long story). Could that be the issue?

It's stopped now... odd.

I find that sometimes happens with programs that use a lot of power on my computer. I guess it takes up more processing power and RAM to shut all it's processes down or something, and that pushes the hardware and screws it up. This is just a guess though, I don't know that much about this stuff. It's never caused a problem though so long as I've saved whatever I'm working on/playing with the program.

I use http://www.tesnexus.com/downloads/file.php?id=22410 for the CTD and it is a godsend! try it out. it requires OBSE but very very easy to install

This is a very common problem. It is caused by a bug in the game engine whenever you have a mod attempting to change content that a previous mod deleted (Official DLC included).

http://www.tesnexus.com/downloads/file.php?id=22410 provides a fix for this.