My 4 yr old grandson brings the same movie every time he comes over, which is 2-3 times a week, and we have to watch it at least once. We have watched it 40-50 times already. He can quote most of it by heart and I find myself able to do the same. So, it must be my favorite too.
"CARS"
BTW, he want to be "Mr. The King" when he grows up. Me, I want to be "Snot Rod" when I grow up.