open a terminal, write
which vlc
VLC 1.1.4 The Luggage
Note the open a terminal note. That is to say, use the command "which".
and this terminal note given by this command has to be placed under settings < general < videoplayer???
Ugh.
1) Open a terminal. (Command prompt, such as xterm, GNOME Terminal, or something like that)
2) At the appearing command line, enter "which vlc" (without the quotes), and press enter.
3) Post here the output you get.