Question Author
Thanks for all your answers, folks.
Not sure whether I could my bloke to do ballroom, Huderon, and I don't fancy dancing with another woman, although I may be able to talk him into some tango.
zbearspirit - I do already walk. I have a dog who needs out on the field a couple of times a day. I don't really fancy class-based aerobics.
Line dancing would be fun - even more so because I think it's just about the most ridiculous form of dance I can think of. It would certainly be entertaining.
Tried belly dancing once - didn't enjoy it.
Body combat/body pump? Thanks Her Highness, China, She-Who-Must-Be-Obeyed, Doll, but it would be up there with aerobics and step - just not me.
It's either going to be line dancing or, as has been suggested elsewhere, tap.