Yoga is the best thing that ever happened to me, besides my hubby.
I have been doing Bikram (hot) yoga for about a year now and love it. It has made me so much stronger and a lot more flexible. You mentioned you like to do stuff alone, believe it or not yoga is an individual activity. If your in a class, sure there are other people, but it's all about you. I would consider taking a class because if you've never done yoga, you may do it wrong or get some bad habbits.
Whatever you do though, give it a try!!!