Next change ~/.mplayer/config with an editor and change the video driver (vo=xv) and audio driver (ao=arts) and remove the last line.
Quickly installing Xine
Download the sources for libxine (xine-lib-1-beta12.tar.gz) from http://xinehq.de. Unpack it (tar xfz xine-lib-1-beta12.tar.gz) and change to this directory (cd xine-lib-1-beta12). Now run configure (./configure) and make ('make'). Install it as root ('su -c "make install"').
Recommended, for encrypted DVDs, install libdvdcss from http://developers.videolan.org/libdvdcss too.
Xine can use the codecs for MPlayer in /usr/lib/win32, however it can't find
after installing to see where it looks for the Real codecs. Either copy or
symlink for Xine to find them.
Quickly installing ffmpeg/ffserver
Download the sources from http://ffmpeg.sourceforge.net/. If the current version is 0.4.6, I recommend using a more recent CVS snapshot because it uses less CPU when grabbing a TV device.
Untar the source package, run './configure --enable-mp3lame' and 'make'. Install as root 'su -c "make install"'.
KMPlayer doesn't work with all the video drivers that mplayer supports.
I tested only xv (X Video Extension) and x11 (Image/Shm). If none work, you
might try the patch for the x11 driver and see if that works for you (not needed anymore for mplayer version >= 0.90-rc4).
You might need to change mimetype settings (Control Center | TDE Components | File Associations) to make sure KMPlayer (or 'Embedded MPlayer for TDE' in embedded tab) is set for all the formats you want to play with KMPlayer.