There's not much you can do with your cd/dvd if it gets scratched but there is a method which I discovered which really works

All you need is:-
Lip balm or Chapstick or Vaseline (any one of these will work)
Lintr free cloth (eyeglass cloth will work)
And most important brain (in a good working condition)

Step 1: Apply Lip Balm

Just apply the lip balm on the cd/dvd in a circular motion starting from the center towards the edge.

Step 2: Cleaning

Now the last step is to clean the cd/dvd with a lint free cloth in the same motion you applied the lip balm.

Yes!! you have done it.
You cleaned a scratched cd/dvd with just two things.