This morning I removed the stupid SP2 from my computer and surprise!
I can burn DVDs and CDs again.
Wait, scratch that.
I can now burn CDs again. DVDs now will not only not burn, they can't even be read by my drive.
Suspecting that SP2 had managed to irrecovably fubar my DVD burner, I went ahead and used goback to add SP2 back to the system, and decided to go out and buy a new DVD burner.