I have heard of lots of different tricks to help play scratched disks: (These will not get rid of scratches but fill the scratched area making the disk playable)
~Metal Polish (Like "Brasso")
~Toothpaste (Not the gel kind)
I have tried the toothpaste and car polish and it works really well. You pretty much rub the product you choose into the disk the same way you would wax a car, lots of little circles. Here is a video.
I have also heard of the DVD/CD repair kits you can buy but have never used them. I did contact our local video store and they can fix the DVD's, CD's or Blu-rays by sanding the outer layer down...removing the scratch. Our local store (Hastings) charges $1.99 per disk and will refund your money if it does not work.
Because most of our scratched DVD's are Disney I also searched the Disney website and found out about their replacement program.
If you accidentally damage, break or wear out one of your DVD's or Blu-Rays you can replace it by sending in your old disk along with $6.95 for a DVD or $8.95 for a Blu-ray. They send you a brand new disk in a new case:) They even replace most disks that have been placed in the "Disney Vault!"
You can find out more about the Replacement Program by clicking here.