Basic options: (complete list in the man page)
-vo <drv>        select video output driver ('-vo help' for a list)
-ao <drv>        select audio output driver ('-ao help' for a list)
vcd://<trackno>  play (S)VCD (Super Video CD) track (raw device, no mount)
dvd://<titleno>  play DVD title from device instead of plain file
-alang/-slang    select DVD audio/subtitle language (by 2-char country code)
-ss <position>   seek to given (seconds or hh:mm:ss) position
-nosound         do not play sound
-fs              fullscreen playback (or -vm, -zoom, details in the man page)
-x <x> -y <y>    set display resolution (for use with -vm or -zoom)
-sub <file>      specify subtitle file to use (also see -subfps, -subdelay)
-playlist <file> specify playlist file
-vid x -aid y    select video (x) and audio (y) stream to play
-fps x -srate y  change video (x fps) and audio (y Hz) rate
-pp <quality>    enable postprocessing filter (details in the man page)
-framedrop       enable frame dropping (for slow machines)

Basic keys: (complete list in the man page, also check input.conf)
<-  or  ->       seek backward/forward 10 seconds
down or up       seek backward/forward  1 minute
pgdown or pgup   seek backward/forward 10 minutes
< or >           step backward/forward in playlist
p or SPACE       pause movie (press any key to continue)
q or ESC         stop playing and quit program
+ or -           adjust audio delay by +/- 0.1 second
o                cycle OSD mode:  none / seekbar / seekbar + timer
* or /           increase or decrease PCM volume
x or z           adjust subtitle delay by +/- 0.1 second
r or t           adjust subtitle position up/down, also see -vf expand

* * * SEE THE MAN PAGE FOR DETAILS, FURTHER (ADVANCED) OPTIONS AND KEYS * * *