Which azo compounds are found in DVD-R and CD-R media?
Each company in the DVD business has their own proprietary twist on the actual dye they use and they don't go out of their way to reveal the structure of the molecule they use.  Also the actual dye used changes fairly rapidly (several years or so) as technology shifts (e.g. higher density, Blu-ray, etc.).  That said, metal-azo dyes are popular today.  A Mitsubishi patent from a few years ago (WO 2006/104196 A1 (10/03/2006)) says "The recording layer contains a pyridone azo organic dye having a 6-hydroxy-2-pyridone structure as a coupler component and an isoxazole, 1,2,4-triazole or pyrazole as a diazo component, coordinated to a metal, such as nickel, cobalt, iron, zinc, copper or manganese." Here is the structure of 2-pyridone (6-hydroxy would be attached on the other side of the nitrogen) and pyrazole.





Here is a link to a Ciba patent that has more detail. And here is a general structure a 2-pyridone-based metal-azo dye