Ok I'm in the crypt and I got the key that was under the water useing the little pole thingy now where do I use the key? PLEASE HELP ME!

If you head back up away from the water room, back towards the stairs with that annoying gap (simply fill it with barrels and crates, I did) there should be a small slot in one of the side walls next to a slightly recessed section with a picture on it. This section is the bottom of a list that comes down when you put the crystal key in the slot. It will take you up into another room. There is a secret room oabove the lift shaft that you'll need to get to. To do this, stand in the lift at the top, press the button, run backwards, jump on the lift roof as it begins it's descent. When it comes up, provided Ratlings or Highland Rogues don't turn up and attack you at the bottom so that you take crush damage until their dead, you should be able to step off into a new passageway (time this correctly, I once didn't and had that whole "Daggerfall" "stuck between the walls" experience again only this time the walls weren't transparent and I wasn't freefalling, merely well and truly stuck.

I was able to climb out but I am still inable to find where to "USE" the crystal Key.

You want to be in the large room which is between the broken stairs and the place where you got the crystal. On the west there is a doorway, examine the left section of the door FRAME (not the door) and you will find a depression which matches the shape of your crystal.

Wyv