Joining a martial arts class. Which one should I join?

Since Iíve met her and weíve been together, itís really turned my life around. It all started when I begrudgingly joined a meet Latin tours trip with my brother, and she just walked up to me. We started talking and immediately clicked. Since then, Iíve quit drinking, started caring more about my health, and have rebuilt my relationship with my stepdad. One thing that my gf and the experience has taught me is to stop being afraid of trying something now, and to initiate change when itís needed.

Now Iím thinking of enrolling in a martial arts class, but Iím unsure on which one to try. Iím a little overweight and Iíve never trained for anything physical in my whole life. Can anyone who works as a professional trainer give me some advice on which one is most suitable for someone like me?