My advice? Turn off auto-save. Seriously, you don't need it. Just remember to save every half hour or so (maybe even every 15 minutes in a dungeon).
The first thing I did when FONV was loaded on my 360 was to go into the options and turn off auto-save completely. It still auto-saves at some key points, but very rarely. I'm about 32 hours in and I've yet to experience any of these issues.
Yes, yes, yes,,,
Turn OFF AUTO SAVE--all 3 of them...the game has a memory leak, please clear the cache every so often like 5 or 6 hours...I cannot believe the world of difference it made in loading times, solved the freezing issues etc...
This is a post from somebody who is close to finishing the game, no game breakers whatsover...