4 wheel drive problems?

I have a 2000 Jeep Cherokee Sport and the 4 wheel drive is command-trac. It's snowing here and I noticed my car was skidding a lot so I wanted to see if puttin it in 4 wheel drive would help. My car is always in 2 wheel drive but theres also neutral, 4H, 4L. I put it in 4 wheel drive and my car was swinging all over the road like going out of control (I wasn't going very fast maybe like 10 mph). Then my stick to change the 4 wheel drive was stuck in a position, finally I got it switched so I put it back in 2 wheel drive, and started driving. However, when I tried to go faster it seemed my car was resisting, then I pulled into the parkin and the turn made my car do a low grunting noise. It just seems like everything is messed up!! Can anyone help