does anyone know what I can do about a DVD that "skips" and "freezes"?

It only does it with one of the episodes on a DVD I have of "The Dick Van Dyke show". I know it's not my player, and the disc played perfectly once, and all the other episodes on it play perfectly.
I've tried wiping it with window cleaner, which I've heard will work sometimes, and it worked on another disc that I was having trouble with, but it didn't work this time.