Hey RowdyRaider, welcome to DC! I'm a College Program alumnus from spring 2003, so if you have any questions feel free to ask away!
I don't think many people here have been characters, let alone worked at Disney (catch me if I'm wrong, ya'll!) I wasn't a character though...I would still love to be.
Two of my roomies were characters. Eeyore, Chip/Dale, King Louie, various Country Bears. I can't really tell you much as far as how to "keep the magic" it sounds like it won't be hard for you to be the best Goofy for other people (btw, he usually flirts with girls, that's a tip!) ;) Keeping the magic for yourself? That's harder. One character-roomie of mine was in tears the first week because the training classes were so sad to her...if you can deal with seeing Piglet's head on a shelf or knowing what the real Mickey Mouse is like on the inside, you should be just fine. :-)
I think DownSouthTigger was a character? You can find him on the College Program thread here. Enjoy your stay and have a great CP experience!