My game wont load

I have played the demo with out any ploblems, so when i got the game today i thought it would not be a problem.,, But when i insert my disc it wont load up to install. i have taken the game back to see if it the disk, but it does the same, it ust makes a noise as if it is trying to start the disk

i had the same problem dont think anybody at SI has acknowledged the problem. So no actual solution yet. I put it in a drive on a different computer and installed it over the network. Also saw someone saying just make a steam account at http://store.steampowered.com/ and u should be able to download and authenticate the game thru steam. Havent tried that last option myself but its worth a try.