Just used IsoBurn to write the file to my desktop. Opened this new Iso file with DAEMON tools lite and it opened faultlessly.

When i burned originally to DL DVD the only setting i recall altering were to allow more than 8 levels.

Unsure how to do the following:-

"If you could create an image of the disc, cut the first 5mb into it's own file and email / upload it somewhere then I'll take a closer look at it"

do you mean the Iso image?

Again thanks for looking.