Re: HELP!!!!
Try contacting Microsoft Support
http://support.microsoft.com/ (dont know what they could tell you but its worth a shot as it could be a hardware issue they might be aware of conflicting with the game... doubtful.. but meh).
Or Lionhead Support
http://community.lionhead.com/
Problem is pleanty of these problems arise within Fable II (its a rather buggy game), so chances are there isn't an easy fix for your problem (if there is one at all).
A basic rundown of small things to consider might be...
Do you have Fable II Pub Games ? (have you recently tried merging a character in it with your Fable II character that is no longer working ?)
Have you checked that the Hard Drive or Memory Card you are storing your Fable II game data on is connected properly ?
Do you have Fable II installed to your Xbox 360 Hard Drive ? (if not, try it as it solves a fair amount of problems with loading and freezing issues according to most of the problems I have read about)
Have you recently downloaded one of the Fable II DLC's ? If you do have one or more installed try re-downloading them as I have heard of peoples game data becoming corrupt after downloading an update... I guess that it just didn't stream through properly and they must have missed parts... rare but still worth a look.
Try clearing your Xbox 360 cache (look up instructions on how before attempting), don't think anyone has solved an issue of game loading or freezing this way but hell why not try.
I'm sorry if none of these fix your problem as I am no expert, but I wish you the best of luck all the same as I know its really hurtful when a character you have worked hard on ends up being screwed over.