Video files

[proudlyfallen]

Anyone know what the hell I need to play MKV files? Media Player Classic gave me this information, but I don't know what to do with it:

F:\Desktop\SHARED\Videos\Coupling\Coupling-Series 1-Episode 1-Flushed.mkv::English (Audio 1)
ffdshow Audio Decoder::Out
Audio Switcher::Out

Any ideas? Anyone?