Jeep stuck in 4WD. Can someone help??

Howdy!

I have a 1993 Jeep Grand Cherokee. I have to shift it into 4WD manualy. Its always been really tight, and kind of hard to shift. I brought it into a shop years ago, and I was told that they are all hard to shift. Well, the thing is... now its stuck. I mean I can get the lever to move, but it's stuck in gear. Now that the snow is melted, the car doesn't like to turn without making a clunking sound, or the wheel having a "wobbling" feeling. I'd love to get this back into 2WD. Is it just a cable, or linkage? It sucks its so cold out now. Thats why If I could get some help, before I go blindly looking at this.

The car has 180,000mi. on it. It leaks some oil, and anti-freeze, and the brake petal is starting to "sink". kind of feels like the anti lock in engaging. I'm starting to wonder if maybe it's just done? :(

Thanks much!