DVD won't play on SuperDrive?

Hello, I just recently bought a superdrive for my 2013 Macbook Air (Yosemite) and I've been using it for burning CD's, but when I put a DVD in (brand new), it shows up on my desktop, but just gives me a bunch of audio files and won't allow me to play it. Is it because I don't have the DVD Player application? 'Cause my Mac won't let me download it. Any suggestions? Thanks xx