so I will be purchasing my first xbox today, and had a couple questions about it since I'm a total noob with them.. first off, is a 20gb hdd gonna be large enough? and what exactly is stored on the hdd> full games? or just like, save files and stuff? secondly, what would be the better games to look at getting currently? naturally gta4 I would like to try out, but what else? thirdly, how should I set it up? Would it be smart to add an external fan around it to keep it cool? maybe its just habit being a PC guy, but I have seen lots of these boxes just up and die when they get too hot..