As long as you stay fluid and open minded, I think boxing and wrestling are a safe bet. It's important to learn other concepts and theories as usual, and to practice theories immediately in order to adjust them or "shave off" the unnessentials. It's important to make your exercises mimic the techniques you'll be practicing (piggyback a big buddy up some stairs is one of my favorites, or maybe makiwara for boxing). In a self defense situation, there is concrete and no gloves. You probably won't recieve any mercy either so it's good to train the way you'll be using it (without pins, or try wraslin' on the concrete a little, just watch yer noggin and the scrapes). All I can say is that I have full confidence in them both and it all depends on many factors, but as for being a martial art, absolotely, in my opinion.