Do note, that OS X's built in utilities and apps like iTunes, iDVD and Disk Utility cover the vast majority of burning tasks most people need to do. But if you must have this functionality centralized, the programs named above will do the trick.
I really like a program to do my burning especially for certain projects I burn to DVD. I have Found Toast the best out there. Burn works for most stuff but I have ran into things it just would not do or did wrong.