That worked a treat, thanks.
I must admit I didn't understand the structure of a DVD-A disc. There were actually 4 different versions of the album on the disc. There were PCM 2ch and PCM 6ch versions which were on the DVD-Audio part of the disc and then there were DTS 5.1 and AC3 5.1 encoded versions which were on the DVD-Video part of the disc. It was this that was confusing me. So I have copied the PCM 2ch & PCM 6ch versions off the disc using Foobar2000. Unfortunately, at the moment, I cannot listen to the 6ch version in full 96khz 24bit PCM glory as I only have an optical S/PDIF link between my PC and AV amp (S/PDIF only supports 2ch's) so I can either listen to the 2ch in 96khz 24bit PCM or let MC convert the 6ch PCM to AC3. Either way it is better than my old MP3 version of the album ripped from the CD.
I've learned something today so thanks for educating me.