Thanks again for your help, Admin.
I don't think it could be a camera issue, as the same one was used for all three videos. All three were shot with a basic digital camcorder (with live sound), imported into iMovie, the CD track was layed over the live audio and then fades were applied. That's all.
I suppose it could be either iMovie importing sloppily, or iDVD not getting the burn right. The kicker is that all three were produced, imported and edited in the
exact same way, so they should have the same issues (or lack thereof) across the disc.
I'm not sure what I'm going to do, if anything. It seems too tough (and arduous) to deal with. I guess I'm just thankful the other two are fine.