Not some hack, but more of a trick.
There exists two media player in Windows. One of them is Windows
Media Player, accessible through Start > All Programs >
Windows Media Player or Start > Run > wmplayer.exe
There's also another one, which is something like
Media Player Classic.
It's named mplayer2.exe.
If you don't want to download Media Player Classic, and at the same
time don't want WMP to bog down your PC, just type in mplayer2.exe
into the Run command.
Of course an easier way would be to just download Media Player
Classic. 
