Looks like you might have been using a hacked firmware with that drive then or the controller on ya motherboard is blocking firmware.
you got a pics of what your drive looks like and on the sticker does it says anything out of the ordinary as in it does carry the pioneer name . eg like Medion
they are normally on @ default [edit having quickly looked at the user guide it has a firewall) it has to as the other options are present also to punch a hole in firewall to let applications work thru port triggering etc.
The majority of Router's will have a firewall.
All the ones I own which is about 20 have one so the Norm should be they have one but it is wise to check if purchasing.
Do as suggested and only get Verbatim but for now try with 4x as ritek dye seems to hate 8x and 6x on all the burners I have they prefer 2.4x(which is not option for you) and 4x
And there it is, READ said option and understanding it. The tooltips that are included are sufficient for most and If you are a more advanced user, research [google] before clicking that option.
http://forums.afterdawn.com/thread_view.cfm/597460
or download these and put all 3 into same folder as your 38.6 meg 1.9s pal ISO and run rightsize.bat this will expand the 1.9s iso to full size ready for burning with ImgBurn onto media of your choice.
WII_PAL.rar
Edit
You should really verify all your burns, especially to the poor media your using.
Check back when say Blutach has replied or another Beta Team Member to guide you thru it.
Look for a firmware update as your drive does not support the media your using.
Or buy an external dvd writer if your drive is a slimline laptop drive which I think it is.