Just a quick update here...
I have found that for me the best way of burning the Saturn back up's is to use Imgburn - I had to install the Radlight4 Ape filter (as a lot of the images contain ape files) from free codecs and make sure I burnt from the cue file - all seems ok for me if I burn this way.
I do get the odd image that wont burn the game music properly - these are normally the images that have mp3 files as part of the image - imgburn states during the burn process that the sound files contain silence... guess I cant have Imgburn mp3 codec set up correctly - not too sure to be honest...? generally there is an ape image alternative to download anyway.
I am using Verbatim CD's burning at 10x speed.
Thanks for the tips Alex - Now got some excellent Saturn games!