Halo: Reach may be plagued with the dreaded "disc read error" problem. It seems that some users are greeted either with a disc read error or a frozen screen when inserting the disc. Installing the game onto the hard drive apparently does not ameliorate the issue. Based on what Bungie forum users are reporting, the problem appears to be related to hardware, as a disc might not read in one console, but will work properly in another.
The cause of the problem hasn't been uncovered. In the meantime, Bungie advises those affected to call Xbox customer support (1-800-4-MY-XBOX) to report the issue. We've contacted Microsoft and will update this post when more information becomes available.
Update: Microsoft has responded, saying, "We are aware of a very small number of customers reporting that their copy of Halo: Reach is causing a "disc read" error." The company advises players to call customer support for "troubleshooting assistance."