I am thinking about getting an Xbox 360, but I really don’t know which one to get, if I should get a hard drive, etc. Anyway, I know there are three kinds, and I don’t plan on getting the most expensive one. So why would I need a hard drive? Is it like a memory card or something? I know that the Arcade version has 256 MB of storage, and the regular Xbox 360 has 60 GB, which I know is a HUGE difference. Is that just, like, game memory storage, or do you have to get a memory card, too? Thanks!