usually when i have that problem, the cdrom drive is bad... have you tried loading them on a different system or cdrom drive?
I did try them in many different drives. But I've got them working now. I burned them again with the original burner, but this time I made sure Nero was set to Disc-at-once. I don't know why it defaults to track-at-once, I thought you always used disc-at-once when burning ISOs? Or maybe that doesn't make any difference and it just worked by luck this time. I did burn them on a slower speed, too.
-Ryan
