Team Wiinja has given some details on how to properly burn a backup of SSBB to a DVD9. Basically, they give information on how to perform the correct layer break. There have also been some confirmations of this working with WiiBrickBlocker.
* his fix doesn’t confirm that 100% of the owners of wiinja deluxe original can play dvd9 ssbb but will help many of them.
* Use High/Excellent quality DVD+R DL (Verbatim DVD+R DL & MEMOREX DVD+R DL tested)
* Use a DVD9 ISO and tested-as-working-properly burner.
* Burn the DVD at a slow speed.
* Open IMGBURN, select to write iso to DVD, select DVD9, click in TOOLS, SETTINGS->Write->Layer Break->User specified and type 2084960. Burn the DVD.
Backlight can be one giant light panel with a diffusor, but recently there's mini/micro LED backlighting, where you can control the light level for smaller areas of the screen, to get better contrast and color range.