After experiencing some problems with Skyrim and my mod loadout after installing Dragonborn, I figured the easiest way to fix everything would be to start from scratch, so I uninstalled Skyrim (and manually deleted the left over files).
I then proceeded to re-download and install Skyrim, Dawnguard, Hearthfire and Dragonborn, and the Hi Res texture packs - all official Bethesda content, no mods.
I can get into the game, and start a new game, but after about 10 seconds on that darned cart, the game crashes.
I'm fairly certain all my drivers and whatnot are up to date, and my computer is enough to handle Skyrim no problem.
EDIT: After deactivating the high resolution DLC and unofficial patch, I was able to play for about half an hour before it crashed.