what to do?

So I have a ton of free time to finish some old projects and start new ones. Im looking at a site where users can create their own accounts, almost like a forum, but it will kinda be like neopets (kinda like an online flash game with build in gamer profiles). I cant really figure out how to explain it. Anyways, what kind of language should I use? im thinking PHP, but not entirely sure. Give me some ideas please!