MY CHARACTER WON'T MOVE!!!!!!

9 hours in and i have gone to great lengths to do all the usual side missions and crafting and buying and selling and leveling up. I go into a cave, clear it out, go outside and boom, my character won't move at all. oh dear. so i load an old saved game. the guy won't move there either. Same problem with all saved games. The guy just walks on the spot, swings his sword, jumps where he is, but will not take a single step in any direction. Xbox 360 version. I have had one guy suggest starting again and hoping it doesn't happen again. But what if it happens 100 hours in instead of 9? Man this is frustrating. Best game ever ruined; unless anyone has any solutions? Please help guys. I've only been waiting 5 years for this game. Having to wait longer is agony.

Thanks. Shay.