Which media player is the best?

I suggest mplayer. I tried a lot of players during
my undergraduate study. But finally I stuck on to
mplayer. Though it is command line oriented and it
does not have a cool interface, still it has the
capability to run any video file.

I think that's what it is important.
Purpose should be important.

I have did many experiments with mencoder.
There are lots of licence software available
and most of the people cannot buy licence software.
So it is better to opt for freewares like mplayer
and VLC. mencoder is very very handy if you are a
power user. The compression utilities are marvellous
and you dont need an expertise to use it.

Just go through the docs, follow the examples
and get going.

Go for mplayer and mencoder.
An alternative is VLC.

I will post some of my mencoder experiments in the
near future.

More info on mplayer

Anand