I can comfortably say that the problem with the monitor is not related to the problem with the DVD.

For the monitor, see the cheat codes section of the wiki and the cheat codes text file that comes with a BitTorrent download. Look for codes that force the resolution and scan rate that you want.

For the DVD: is this a low speed burn? (no more than 4x)? Do you trust the quality of the media? Are the drive optics clean? If so try the nodma cheat code during boot (seems unlikely to be needed for a DVD however). And, of course, I'm assuming that you verified the md5 sum of the iso file, if not before burning at least before posting.