[SallySimpson]

I'm pretty sure if you had ripped again the file you got with Decrypter with Shrink to reduce the size, it would have worked.
Do it again. Decrypter is used to "remove" the protection and some encoded/encrypted stuff, mainly, and Shrink is used to get a file which fits to be burnt with Nero normally.
You say you have deleted the file cos it was too large to be burnt normally, so rip the original one again with Decrypter, then resize it with Shrink, you won't get any more the error when reading due to the protection. I hope...