Can you read the optical media on another computer and copy the GHO file from the DVD onto the hard disk ?
If you can recover the files from the optical media to hard disk then you stand a chance of recovering the data, but if the DVDs are not readable then there is a good chance that you have lost the data.
I have had experience with bad media in the past, so before writing any DVD I have a careful look at the optical surface to see if there are any visible defects. It is not uncommon to find some media with quite large defects plainly visible on the surface. They may work long enough to pass a verify right after the write, but fail soon after.
My own preference is to back up to locally connected USB hard disks where possible, as these are much more reliable that optical IME.