Can this disk be saved?

I copied all my pics and doents to a bunch of DVD disks and when I re-inserted them in drive they showed my photos,videos and files so I thought I was safe. I have to Clean my hard drive totally and now when I try and play them back it shows nothing. They do look like they have been burned on properly. Can these disks be saved? Please answer honestly I have some pictures on here that were irreplaceable.