Welcome to the club!!! You'll love it here, lots of good guys/girls with good tips.
Here are my answers to your questions:
The AC only comes out of the floor vents (is cold). ANS. Cold is a good thing. Vent doors not moving. Floor discharge is default condition. In Defrost, there should be A/C & Heat come through the defrost vents.
On hot, it only feels like outside air coming in, and has faint smell of coolant. ANS. Air temperature not moving and possibly heater core leaking. Windshield would fog up a bit right after selection of HOT DEFROST. Telltale sign of core leaking.
Radiator low lamp will come on when engine at normal operating temp, and radiator is full. ANS. Usually the light comes on if coolant reservior is low on fluid. Check Engine light will come ON if overheated engine.
Someone said I might have a vacuum leak? As vacuum is used to control the valves? This made sense because the AC use to do this when I had the peddle to the floor. ANS. Very possible.
I can here a slight hiss coming from the area under the hood were the heat an AC lines go in to the unit under the dash. Never noticed it before, but I was never listening. ANS. Very possible there might be a vacuum leak, as in hose off, broke, or the vacuum reservior is leaking.
Reading your problems, they seem to stem from a vacuum problem. A reservior is evacuated and holds vacuum for those wide open throttle events. If there is a hole, vent & temperature doors will not close/open.
You've done some good troubleshooting, now be industrious, and go find the hiss and I bet this is the location of the problem. It should not hiss at idle, or any other time.
Everett "OBJECTS IN THE MIRROR DISAPPEAR UPON RAPID ACCELLERATION"