This is a good catch-all media player. It'll play almost any audio or video file. Its default interface is not pretty (though it is skinnable!) and it gets really complex. It can even do some very light video editing if you know its features well enough. I personally like Media Player Classic with a good codec pack, if you want better quality video playback, but I still end up using VLC in many cases because I know it just works.
This is the media player for you if you'd rather enjoy your media instead of chasing down codecs. It just works, and you'll seldom come across a format it doesn't support. I prefer the UI of KMPlayer so try both and see which one you prefer. You can't go wrong either way.
VLC is a free and open source cross-platform multimedia player and framework that plays most multimedia files as well as DVD, Audio CD, VCD, and various streaming protocols.
While neither the VideoLAN team nor Puget Systems charges for the installation and use of this software, we do encourage you to make a donation to the developers if you find VLC useful. You can do so by following the directions on the VideoLAN donation page.
Configure a quiet custom PC with the VLC.