The Last Resort:
If your system is completely screwed up and you're thinking of reinstalling the operating system from scratch to fix your media playback problems, here is a last resort action you can take prior to doing this. Notice, this action may damage media playback on your system, but if you follow it carefully, you should be ok. Just make sure to read all the instructions carefully and don't skip any steps.
Here are the series of actions you will need to take in order to reset your media playback settings to their default values (As they should be after a fresh OS install).
1. You will first need to obtain Zoom Player v3.10 or newer.
2. Run Zoom Player and open the "Options / Filter Control / Management" tab and click on the "Registered Filter Manager" button.
3. Select all the filters in the list (highlight the first filter, hold shift and press the End button on the keyboard).
4. Press on the "Unregister Filters" Button.
5. Close Zoom Player.
6. You will now need to re-register the filters that come with the system on a fresh install. To do this, run
this batch file.
7. To restore DVD Playback capabilities without reinstalling the DVD Player, you may also need to register the DVD Filters that came with your player. You should be able to do that using Zoom Player's Customized DVD Playback interface by selecting the decoders you use and pressing the "Register" button.