I would do what you want to do. Go with what you like to work with. Buy what you want. Don't buy into a fad if its not what you'd like to work with and keep, because all it will do is ensure your failure with it. If you like Corn Snakes more than Ball Pythons, then buy a Corn Snake. If you like Ball Pythons more than Corn Snakes, then buy a Ball Python. Choose what animal you like.

As for what you will do when you go off to college; no most all Dorms I know of won't allow animals. If your unsure of what you will do with the animal when you go to college, then simply hold off on buying it. Anything can happen from now until you get your life on track and really going. Take me for instance. I had quite a few Burms as well as an Afrock, a couple Ball Pythons, and a Retic, then when I turned 18 I enlisted in the regular Army. I had to sell my whole collection. I was unsure of what I wanted to do at the time. If your unsure as of right now, simply hold off for now. Trust me it can wait. It may seem like you can't wait, but you can