When you open 'My Computer' and open the drive with that disc in, what EXACTLY do you see? Is there just an empty window or do you see the folders but you can't then go into them?

Have you tried creating a new image from the same files to see if it happens again? You can just build an ISO and then mount it in DAEMON Tools to test it, there's no need to burn another disc.

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.

There must be some sort of file system problem if Windows won't parse it and that 5mb should contain everything I need.