If your still struggling with ripping your DVD try Alldj DVD Ripper, I have used most programs and this seems to work with most DVD's giving many options for use which may or may not be of use to you. Will look around and see what else to suggest if needed.DVD Fab Decrypter (free or platinum) is the best ripper.
If that doesnt work, you need to fix the damage. Either clean and fix (CD/DVD cleaners & polishers in all computer shops, PC world etc) or use something like isobuster to recover / ignore the damaged bits.