Polish the CD scratches with a soft cloth and neutral-colored car polish. Gently use straight strokes across the surface of the disc from center to edge to buff out the scratches. Repeat as necessary until the scratches are no longer apparent.
Use version 8 or higher of Nero to attempt a CD rescue. Put the CD in the writeable drive of the computer. Select the "Copy CD" option. Nero attempts to read the disc and write the contents to a folder on the hard drive. Once Nero finishes writing the contents to a folder, burn a new CD from the copy saved in the folder.
Use Nero 8 "Rescue Agent," which is included in the software, if the "Copy CD" command is unsuccessful with your scratched CD. Open Nero and the Rescue Agent module. Follow the onscreen instructions to scan the CD while Rescue Agent attempts to read and recover all available data. Continue to follow prompts while Nero adds all recoverable information to a file on the hard drive. Burn a new CD from the recovery folder on the computer.