I believe you are jumping the gun in assuming that your DVD Burner is â€œdefectiveâ€ and needs replacement.
In you initial posting you have provide very spare information for Forum Members to provide any meaningful assistance.
Provide the Name(s) and Version Number(s) of the software program that you are using to make your backup copies of Commercial DVD Movie Titles.
Provide any Error Code(s) and the exact complete Error Narrative(s) you receive when you experience your problem.
The solution to your problem could be something as simple as up dating your DVD Burner Firmware to newer up to date current firmware but until you provide detailed information it is difficult to determine the actual cause of your problem.
You havenâ€™t provided any of information concerning your Note Book Computer but many DVD Burner Manufactures make replacement Note Book Computer DVD Burners. Normally there should not be a problem installing a quality internal DVD Burner in a Note Book Computer.
The preferred option would be an internal DVD Burner for you Note Book Computer. Internal devices always perform better than an external device. There can be data transfer problems with external USB and/or Firmware devices. Using an eternal device has some disadvantages over an internal device. With an external DVD Burner you have other extract item that you have to tote around. Also a Note Book internal DVD Burner is less expensive that a USB and/or Firewire external DVD Burner.
Before making a purchasing decision strongly suggest visiting the CD Freaks Optical Drive Forum (http://club.cdfreaks.com/forumdisplay.php?f=61) and research what DVD Burner meets your requirements. There are many choices and it prudent to do some research to ensure that purchase a quality DVD Burner.