Martial arts experts - which one for an unfit adult novice?

[doubleeggandchips]

...I would like to try something new, plus desperately need some exercise, and having recently seen a friend's DC get his Tae Kwondo black belt (aged 10!!), would like to try a martial art.

So, which type do you think? I am not very flexible any more, but used to enjoy yoga so reckon it could be improved. In my ignorance, I quite like the sound of aikido having read up on a few different MAs on wiki, especially the focus on ki/chi.

bump...

Aikido is very thoughtful although still good exercise. Go and watch a class. It's very different from tae Kwan do.
I did judo and jiu jitsu. Loved them both big they're very full-on.
Imo the class/teacher/dojo matters more than the art in terms of gelling so go and visit a few and ask to watch - good dojos will be happy to let you watch or join in for free before you decide.

Thanks museummum, I will search out an Aikido class then