You can try using one of the many Disc Dr. devices that are out there. Best Buy probably has one and it might help to get the disc back in working order.
If you haven't created the ISO yet you can try using IMGBurn to create an ISO of your disc. Small app, easy to use. Also, will allow you to burn to disc.
With the ISO you can download and install Daemon Tools or Alcohol 120% to mount the image and run the installer.
Considering these apps aren't illegal and you are using a disc that you own, I can't see how it would be construed as piracy.