Now because OMXPlayer is still very new, it is still very basic. So basic in fact it's key bindings (for play/pause/stop/quit) only function if the program is launched via the CLI. Knowing my Fiance and friends who often use the media PC would give me no end of grief if they had to open a terminal to play movies - I set about finding a solution. Today I'd like to share that fairly simple solution with you!
To allow users to simply "double click" on a media file via the file manager and have it open in OMXPlayer you need to create a .desktop file for OMXPlayer. Open a terminal on your pi and run:
Exec=omxplayer -o hdmi %f