Thank you all for the advice. I've installed PHP, Python, and RoR. PHP took the longest to get up and running properly so I would have just wasted all that time if I didn't at least try to use it right? Also just looking at the number of applications that use PHP versus the others, I guess I will start with that. I used to know HTML/CSS pretty well, but that was 5 years ago. I never went much deeper into the web development world.
Again thank you all for your advice.