What's the best way to clean a DVD?
After having tried everything else, I could restore a DVD to a working state with Brasso metal polish.
You apply it in circles from the center of the DVD to the edges and let it rest for a few minutes. After a while remove with a soft cloth and most scratches should be gone.
It may sound crazy, but you can clean and remove minor scratches with a banana. I've used this technique, and it does work.
You can get special fluids for this and a whole host of items to do the job, but in reality a t-shirt has served me well for years :)
as a small aside, clean it inwards to outwards, not in circles as it would grind any debris in the directions of the tracks.
... fixing scratches is anouther issue completely.
Dip a soft cloth in Isopropyl Alcohol/Ethanol/Methanol and gently wipe the surface.Always wipe the disc surface in a non-radial back-and-forth motion (from the center hole to the outer edge).