Faulty DVD disc.

It could have just been a bad disc and you should take it back to the store that you got it from. If you still have the receipt take it back to the store. They will give you another one. Now if you have had it for a long time I know there should be something in the papers that came with the dvd for you to contact or email someone about the dvd being bad. Every now and then you will get a bad dvd that's not your fault. So contact the store or the distributor to get another dvd.

I had a problem with one of my DVD's in that the whole movie was missing the menus where set up but the actual movie was missing, I went with the receipt within the time stipulated and they checked to see if it wasn't my player that was causing problems and they changed it for me. I have had another case in that the DVD I bought was supposed to have extras and when I went to see it, all the extras were missing but when I went to ask if they would change it they said that as soon as the cover was removed they would not exchange it and unless there was something structurally wrong, I would have to talk to the distributor. I did not go further as it was on promo and a friend had the same problem,the distributor said that it was a misprinted batch and could not do anything. It will be difficult, to exchange but you may be lucky.

If it is only that track that stick it may be a scratch on the disk, there are cleaner on the market that help and allow the disk to be played properly unless the scratch is too severe.
If the whole disk has a problem it could be the DVD player.