Favorite- Hamstrings, quads and the entire back Least favorite- Shoulders, chest, and calves (the first two because my shoulders are giving me a lot of problems lately, so I have to baby them and calves because they are my worst body part.
I would say that my favorite body parts to train are my biceps and calves. Shoulders too. I enjoy shoulder work as you can see the results almost immediately.
I hate leg day, but i do it. Bad knees make it tough to get excited about training legs.