Disney has a replacement program, but it will cost you $ to get a replacement, if it is still in print. Most older Touchstone and Hollywood Pictures titles have since been licensed out to Mill Creek and Kino.
I have found that Warner is pretty good about replacing defective discs, even years after they were purchased, provided they are still in print. Just fill out the form at https://www.warnerbros.com/customer-service, and someone usually responds within a few days. They may ask for a receipt, but...