Judo- Pros: in terms of self defence, may work well, if they are wearing a shirt. Judo uses a lot of the Gi (I believe that is how you spell it). They allow you to throw people left and right if they are wearing clothing you could use. Also, of those you listed, I believe it is the only ground martial art. A fight will only go to standup if BOTH fighters want it in striking. If someone wants the ground, it's going to the ground.
Cons: If they aren't wearing a shirt, your not in very good shape. At all. You can still use shoulder grabs and whatnot, but still, your in bad shape.
Karate:
Pros- Fantastic Blocks. I fight Karate people all the time, (for sparring, of course) and it's just SO DANG HARD to land a punch on them. Also, although i'm unsure of this, they teach you how to get back into striking range (a friend who does it told me).
Cons: Not so great offence, i've noticed. I mean, it's good, but not as other martial arts. Also, as I said earlier, I'm unsure if they teach ground fighting/defence.
Body type: Any will do. Although generally, I see a lot of small guys there, not because you need to be small but because they want to defend themselves.
Taekwondo-
Pros: When I spar with one, and they hit me, I feel like I have been hit by a charging sumo wrestler. Actually, that's an exateration, but they have amazing kicks. Flexibility is also good, so if you aren't flexible, consider taking taekwondo, because they teach a lot of flexibility. They also have ok punches. I mean, not great, but ok. Generally, though, they love kicking
Cons: Very, very, simple minded. Pretty much just kick, kick, kick to the point of unconsciousness. NO ground fighting is taught at all, and clinch is non existant, with the exception of a few pushes to get back into kicking range.
Body type: I'm told short people do well, because they tend to be a bit faster.
Kung Fu: Heavily emphasized on physical fitness, those guys are in amazing shape. I have seen Kung Fu masters break iron bars on thier head, throw a needle through glass at about 20 feet distance, and even stand on their head for 2 minutes. Which would normally break his neck.
Cons: Usually, they use pre-recorded attacks, so if anyone else your fighting knows kung fu, there is a good chance they can block your attacks. Also, I doubt (Though unsure) ground fighting is taught.
Body type: Any will do, but bigger is probably better.
Hope this helps!