Advertising-supported GOM player is famous in Korea, but what if you want to try out something different?  Which media player can you trust?  Two which we recommend are:

VLC media player (it’s available for so many different opperating systems, and it’s available in Korean too!):

http://www.videolan.org/vlc/

and Quicktime Alternative with Windows Media Player Classic:

This is a double pack, you get the Quicktime video codec, so you can watch Quicktime videos without having to download Quicktime, and it comes with a tiny but powerful media player called Windows Media Player Classic.  It looks like the old Windows Media Player, but it’s MUCH more powerful.  It’s really impressive how many options they can pack into such a small application.

http://www.free-codecs.com/download/quicktime_alternative.htm