Picking up a used xbox 360

I'm buying a 360 off an internet ad and I'm picking it up thursday. I just have a few questions

1. Without the original receipt, can I still send it in if it gets broke.

2. Is $300 a good buy if it comes with hdd, lost planet and hd player and controller.

1. Not sure.
2. You can get a new Xbox for 300$ HD-DVD is extinct now, and Lost Planet is like 20$. I'd just buy a new one, so you don't have to worry about it breaking.