I can finally burn DL discs with NO problems now. In the end the solution was to use the right DVD burner. I had stuck with Sony forever, but I am now convinced that the Pioneer 115D is the way to go. Dark Jedi pointed me towards this model, and it is absolutely the best burner that I have ever had! Best of all, I picked it up for $40 on ebay.

If you are having problems with burning DL discs, and it doesn't seem to be your software choices/setup, I would highly recommend picking up this burner.