Hi, Silky. We're almost neighbors. I'm in Philadelphia.
Years ago, when I was thinner, I folk danced about 3 nights per week. It's great exercise.
If you're open to the idea, you don't need a partner. The nice thing about it is that you can do as many dances in a row that you want and then rest if you need to. The people who go are really nice.
Contra dancing is probably the most mild, in that it's just a little more exersion than walking. There used to be a contra dance in Yardley every month and there is one every week in Philly, but I haven't been in years, so I'm not sure. (Contra dance has similar steps as square dancing. It's like couples Irish, Scottish, and English. You have a partner, but instead of dancing in a square, you dance in long lines of couples.) They teach you all the steps before each dance.
There's Israeli dancing in NE Phila on Sundays. On Tuesdays in the first boathouse behind the art museum, there is international folk. There are also dances in Princeton. They teach dances for the first hour, usually.
Check out
www.folkdancing.org or The Folk Dance Council of the Delaware Valley for more info.