"Please place this disc into an Xbox 360 console" wtf? it is in a 360...help me!.?

Ok, so heres the deal...My xbox has apperently forgotten it can play games and thinks it's a DVD player now. Every time I put a game in it, it tells me this disc belongs in a xbox 360...no duh...My friends have told me to clean the disc, blah blah blah...but GTA is brand new and is in perfect condition and yes, I've tried other games, its not just GTA.

Also, the box is able to read the disc, if it wasn't able to, it wouldn't be able to tell me what to do with, it can tell what's in and where it needs to go, basically, it knows its a game, and can't play it...It still plays DVD's just fine and thinks all my games are DVD's...at the bottom of the dashboard it tells you what game is in, yeah you guys no...well, mine always says DVD.

Anyways, if anyone has seen this before and knows if there is something that can be done that doesn't involve lots of money, please let me know.