This program will help you recover disks with bad sectors.
You can recover files as well complete devices.

In case if finds sectors which simply cannot be recoverd, it writes an
empty sector to the outputfile and continues. If you're recovering a CD
or a DVD and the program cannot read the sector in "normal mode", then
the program will try to read the sector in "RAW mode" (without error-checking
etc.).

This toolkit also has a utility called 'mergebad': mergebad merges multiple
images into one. This can be usefull when you have, for example, multiple CD's
with the same data which are all damaged. In such case, you can then first use
recoverdm to retrieve the data from the damaged CD's into image-files and then
combine them into one image with mergebad.