I have noticed there are over 1000 keys in my inventory. So, I'll drop those..
Just to make sure you understand, don't just "drop" the keys. If you do, at best, it'll take the game a lot longer to kick 'em to oblivion (so to speak) and, at worst, they may not cleanup at all. Hence, the suggestion that you move (i.e., store) them to a generic corpse (not one from a uniquely named NPC) as they are the fastest to cleanup (three days in-game max).
Thus, if I were you, once you can get your game loaded, head out and kill the first wild animal/creature you find, then move (store) all but one of the duplicating keys to the corpse; then head back to a small intererior cell (a home if you own one, or an inn) and wait there for three in-game days (four days maybe to be sure). Now head back to where the corpse was, and if it's gone, you should be good to go.
Now save your game. Quit the game. Power off the console. Power it back on and hold down the both the LB/RB and 'x' button (what button is that on the PS-3? ... just whichever button you'd use to sheathe your weapon) to clear the game cache. Once the game loads, load your save. It should load lickety-split compared to what you're -- now -- used to. (Note: because you cleared the game cache, some of your menu page accesses and initial cell loads may be slightly longer than normal as the cache rebuilds -- though they'll still probably seem lightening fast compared to what you've been experiencing.)