First off I'll stick to the topic.
If your after discipline and fitness you might want to look at the traditional martial arts. They are really intense (assuming you get a good teacher) in the discipline factor, with drills and Kata, and the fitness will come with that. The more modern stuff (BJJ, MMA, Krav Maga) are very hands on and combat based, so expect a lot of sparing or at least sparing focused drills. Having said that, the exercise and fitness aspect of the Modern martial arts is going to be a lot better. My advice is to go around to your local schools and try it out. Most of them will offer at least 1 night free, so have a go and see how you feel. I did that and it really helped. In one week I did BJJ, MMA, Muay Thai and Wrestling, I found out exacly what I could and couldn't do and I found out what I want. Now I'm training twice a week and loving it.
To add on to that, I have found out that every (assuming you're school isn't shit) Martial Art is going to give you the same overall thing. Don't get me wrong, the skills are going to be totally different, Taekwon do will teach you how to kick, BJJ will teach you ground work ect. but the fundamentals are going to be quite similar. You'll learn how to throw a punch, your confidence will build and your fitness will raise. I'm pretty much saying any (again, assuming your school isn't shit) Martial Art is going to help you.
So, good luck with finding a school, let us know how it goes. I do enjoy chatting about this stuff.
Mumorpuger said:
So, There's a debate that Bruce Lee, if he were in his prime and alive today, would be terrible at MMA fighting. I disagree, because he pretty much invented MMA, and would sweep the floor adapting to the new styles. Anyone have input on that?
I think that, after about a year of training he would destroy. But, if he came back right now and stepped in with someone like GSP, he wouldn't do very well. Its a totally different set of skills and totally different kind of fitness. Bruce Lee is amazing, but these guys are pretty amazing too. But yes, if he came back and started training he would learn really quickly and do very very well.