If you have another DVD drive besides your DVD burner, place the original disc in the other drive. In DVD-A choose Make DVD, Burn, User previously prepared project. Browse to the drive containing the original disc. Put a blank in the burner and burn.

If you only have one DVD drive, or the second one isn't fast enough to read the disc as fast as the burner burns the new copy, simply copy the AUDIO-TS and VIDEO-TS folders to a directory on your hard drive first, then burn from this directory.