If your xbox can't read a DVDR of a movie or a backed-up xbox game, make sure you have a DVD-R disk, not a DVD+R disk. This might be common knowledge for most, but for those that don't know, now you do.
This varies from person to person, depending on what drive they have in their box and how well their laser is running. Many Xbox drives can read DVD+R discs, the only two that give people problems [bold]sometimes[/bold] are the Thomson and Philips. But many still say DVD+R works just fine in those drives. The Samsung and Hitachi drives read DVD+R 99.9% of the time, and the .1% that claim their drive cannot read DVD+R more than likely have a laser problem.