A/C loud noise and powerdrain

I have a 95' Chrysler New Yorker, and I've noticed that the A/C takes away a LOT of power from the engine. Not only that but when I have the A/C on and I press on the gas, the engine makes this loud noise like it's really struggling. Think of the noise your car would make if the wheels were slipping on mud, and you get an idea. Also when I say power loss, I really do mean a big loss. The car's acceleration is almost halved with the A/C on. I pay attention to this because this car has a powerful engine and whenever I get a chance to floor it, I do. With the A/C on though, not only it accelerates real slow, but if I give it more gas, the engine revs higher, but the car doesn’t move faster. Always making the loud noise. Everything runs perfectly smooth when the A/C is off. The A/C runs nice and cold, and all the electronics work good, but it does leak refrigerant.

Any ideas?

By the way I know some about cars, but I know nothing about the air conditioning system so please be as verbose as you can.