Basically having played a lot of GTA V, now I'm going back to redo missions and mess about.
I thought I'd try 'hunting' with Trevor, and when I try the strangers & freaks mission retry the Xbox 360 informs me that it needs to make a 'restore point' and is this ok? I click yes, the message repeats until I click 'no' and then it reverts to the character, immobile; unable to move, act or even be hit (it was fun listening to a biker near the bar insulting him for about 10 mins...)
I also have a similar problem where the game works just fine until I try to access the stock market with any character, after which almost all functionality is lost; and the game becomes 'drive around and shoot things.'
If I did not have such a profound love of this; it's cultural references, it's humor, and all of its other elements, it probably wouldn't bug me this much; but I do and would really like to not have these problems without having to begin again from the very start...