1996 Jeep Cherokee car shakes when hit a big pothole.

I have a 96 jeep cherokee it sometimes shakes when I hit a pothole, shakes pretty bad where I have to pull over to stop it. Another quick qustion I was coming home from a bad winter store and got stuck in a ditch shaked later on that night when I would hit 55 or over, im thinking the drive shaft maybe got some mud and snow stuck in there, the towtruck driver said it was so cold that my tires were frozen to the ground under all the snow. Ohh this site is going to my favorites I love what you did with this site very informative and I love how you can ask a question, you really out did yourself on this, must have taken a long time.