95 Jeep Grand Cherokee stalled

My Jeep has been acting like its going to stall when I am coming to a stop. It idols rough when I am at a stop only when it is in gear or when I am backing up. As soon as I put it in park it idols fine. It has only stalled on me once so far and it was when I was backing up slowly. Also sometimes there is a squilling sound like a belt or something that happens sometimes when I start it up, no matter if I had been driving it for a while or if I just started it early in the moring. I have only had it for about 2 months and the O2 sensor was replaced when I bought it because of codes that were read. If you could please give me an idea of what could be wrong. My husband is a mech. But is currenlty in Iraq so I usually dont have to ask for help. Thank you