Back in the days when DVD's were the primary disc format Microsoft wanted to charge you for their MPEG-2 decoder component if you wanted to play DVD's with Microsoft's bloated Windows Media player. I'm not sure if they tried something similar with HD DVD or Blu-ray disc playback when those formats were released a few years later. Personally I used DVDFab's media player as I was one of the beta testers
In more recent times Microsoft used to supply an H.265/HEVC decoder with Windows 10 but quietly removed it but these days nobody needs to use Microsoft's bloated Windows Media player!