Zumba!!!!
Zumba is so much fun! I go to a class at my local YMCA and we have a participant who is 70, she keeps up and has fun with the rest of us. Only difference is she doesn't jump as much or do the really quick steps, the instructor gives alternative steps so anyone can do it! You should try it out sometime I've never had so much fun exercising. I easily burn 500 calories in an hour so it is well worth the effort!