Game Freezes Before Title Screen

I own Mass Effect 3 for the 360 and it keeps freezing right before the title screen. It wont install on my 360 either, it gets to around 41 percent before an error pops up. There shouldn't be a problem with the disks, last time i used them it worked fine, but for some reason now it won't read either of them correctly. Is there any way to get them working again without having to buy another copy?