Console help! What is going on? What am I missing?!

[Clo]

I don't know where to go with this, probably here, I'm too blindingly frustrated right now.

My friend lent me his X Box 360 so I could play a lot of Final Fantasy XIII over my long weekend. I reached Disc 2 last night, and Disc 2 was working fine the whole while, but I became tired and shut it off. Sleep. Next day. Go to play some XIII. But Disc 2 is now not working -- which makes no sense to me, because how could it have got scratched/ruined over night just sitting in the X Box? I go and clean the disc, but this doesn't work either, except now it's reading as a Mixed Media Disc which, considering how it had been working fine just last night, results in a whole lot of on my part. My frustration leaves me to repetition, and I keep opening and closing the tray, and THEN, the game does load! Except now it's getting frozen in that little recap of the story that occurs when after you load the data. Repeatedly. I can't get past that part.

What is going on! I'm not an XBox owner, I don't know that much about them. All of the other discs to the game work, just not Disc 2. NOTHING happened to this disc, why is it not working all of a sudden!? I don't even see any scratches on the back of the disc. ARGH.

Help.