Should I take Tae Kwon Do, Shaolin Kempo, or Kung Fu?

Kung fu but that would also depend on what style of kung fu, and how well the school teaches it. I have no interest in learning the other two arts you mentioned.

Kempo or kenpo is a mixture of Chinese, Japanese, and Okinawan martial arts. Shaolin kempo can trace its roots back to kajukenbo. Kajukenbo can trace its roots back to James Mitose's kosho ryu kenpo/kempo( as well as four or so other martial arts). James matose ( who is responsible for bringing kempo/kenpo to America) learn from the Yoshida samurai clan/family. Shaolin kempo very self defense oriented. Fast strikes to vulnerable targets. It is an interesting mix of kung fu( not sure which style exactly), karate,and jujitsu. Taekwondo has great kicking, but tends to put a bigger emphasis on the sport aspect. Kung fu is a blanket term for pretty much any Chinese martial art. So it really depends on what art they're teaching and weather that instructor puts an emphasis self defense or not. Fyi if you do some online research about kempo/kenpo you will find a lot of different opinions.