Vimeo Choppy playing full screen sometime small window

[shengchieh]

I suspect you have processes running that you do not use.  For many media programs, it is not enough to click "x" on the upper right corner.  You must quit, i.e., file -> quit or ctrl+Q.  Look at the bottom where your panel is.
Do you see stuffs running?  If so, right-click -> quit.

If you don't see stuffs running, open up a terminal and type

ps -ef

and see what is running.  Use pkill or kill to kill dead processes.  Use the manpage to learn about these commands, i.e.,

man pkill
man kill

Sheng-Chieh