Umm sounds very similar to the "Frosgard" crash....that several have experienced..
IMO that is caused by attempting to enter the "City" map after going somewhere local in the "Frosgard Area" that the SW did not expect in it's design. The resulting mini saves then cause conflict. I now make sure that on my first entry to the city I do so without any explorations. e.g Dont poke nose into Giant's castle before given the quest...Could be same for Dranghiem...
The other area where I have had a crash once was those big noisey gates at Gumberland..I put that down to sound problems..but perhaps I did go collect a certain hair brush before tasked to do so..fancied a stroll along the beach before booking in with the Jarl.
