I'm a 1st degree black belt in Tae Kwon Do... I'm also a kickboxer, not officially anymore because of a lack of funds though.
I'm also trying to find out about some Brazillian Jiu Jitsu classes.
Personally, I believe Muay Thai, Boxing/kickboxing, and Brazillian Jiu Jitsu are the only martial arts that will make you a good fighter and give you enough technique and ability to defend yourself well.