Ok so I have been messing around lately with downloaded programs, and was wondering if there are any good open source games like Battlestar Galactica or something that I could modify. Be wary though, because I'm not the most proficient programmer, and am not very familiar with really high-level stuff.
I just want to say that "Modding" is to "Coding" what "Interior Design" is to "Engineering". If that's the kind of thing that you enjoy then cool, it's fun for you and it brings joy to hundreds of people at a time. But don't think of it as an intermidiate step that you need to take in order to learn programming. There are few aspects the two actually have in common.
Depends what you take 'modding' to mean. I've seen some really cool mods - stuff like HLDJ (which allows you to play music over your mic during Steam games to annoy people).
When i was in college, i took the game Battle for Wesnoth as my final project for my open source programming class. It was a breeze working on this one as there are a lot of tools available online. Their community is very dynamic and they would really encourage participation. They will be part of the Google Summer of Code 2011, so that can speak much as a guarantee.