Problem with backup games

I'm using QoobChip Pro, with 1.3c BIOS. I've tried many DVDs, here's a list of those:

Verbatim Advanced AZO+ DVD-R 16x
TDK DVD-R 8x
TDK DVD-RW 4x
Biltema DVD-R 4x
Maxell DVD+R 16x

but none of these work. The laser was set to 413, but I chanced it down to 209. When it was at 413, the TDK DVD-R worked and showed the Nintendo logo, but then it jammed. All other DVDs, now and before the laser adjustment, give either a loading game screen or black screen with green lines near the bottom of the screen. I can remove those green lines with changing the DRE workaround level, but then GC shows disc read error.

And now the questions: what causes those green lines, and why none of these DVDs work?