Big mistake to copy on the fly as any read error will result in a wasted DVD, a Dual Layer one in this case.
If it's a DVD movie then rip it to the hard drive with DVD Decrypter as an ISO image & then burn that image with the same program or ImgBurn.
If it's data with Nero copy it to the hard drive by using the image recorder as the output device and then burn that image to the burner.
You really must enable DMA on the DVD-ROM. Try downloading the VB script in my signature & running that with Explorer. That should fix it.