The only kind of dancing I'd ever do in front of people is a waltz or a cha-cha. That's all I remember from the dance class we took many years ago, and I'm maybe a 3.5.
Any kind of "free-form" dancing? I'm not even going to try, so I'm a big fat zero.
My favorite kind of dancing I've ever done was square dancing. That was some great exercise! I only wish someone would come out with a cool, non-hillbilly version of it that would become a popular form of exercise.