hello, from what I've read on these forumns I should be able to play this game. I have an xbox 360 slim harddrive, but the game will not install. I'm asked to download the game again, but I have a disc. I've read that I should have a button to install but I only get install or eject. I have tried two different copies of the game with same results. Is there a difference between an orginal xbox 360 harddrive and an xbox 360 s harddrive?