Encoded the movie Scooby Doo And The Ghoul School into MKV h.264 format with English, French, and Spanish audio and English, French, and Spanish subtitles as well.

For playback all you need is the proper codec if you don't already have it. 
Combined Community Codec Pack (which I prefer) or the K-Lite Codec pack should give you all you need and more to play these back.

You should be able to hear audio just fine if you have one of the mentioned codec packs above. If you cannot hear any audio and do not want to install a codec pack for some reason, then you do not have and need the nero aac audio codec. As of today it can be found here. 
http://www.nero.com/eng/downloads-nerodigital-nero-aac-codec.php


SCREENSHOTS

None this time