The original 20GB didn't have the chrome accents. It's either a 60GB or later 40, 80, or 160GB. edit Either way I agree, go for a slim. The pre-slim units are probably a bad idea at this point unless you can get one for a ridiculous deal.
Thumbs up on getting a pre-slim unless it's a great deal. My phatty had video processor problems that would make black blocks whenever there was fire on the screen.
I ended up buying a slim and reboxing the phatty so I can fix it at a later date. haha