Are you folks saying that if I burn a file to a CD/DVD with a checksum, then read it back, the checksums won't match?
If that were true, no one would ever sell software on CD/DVD.
My home archive is composed of 1) The hard disk image. 2) another hard disk image in a safe deposit box and 3) a stack of DVDs. I trust the DVDs as much as I do the rest of the media.