I use the flowplayer plug-in to play my videos (which are .mov HD files) but the screen size cuts off part of the video. How can I change the screen size, or can I?

I found a patch tht purports to do this but I don't know what to do with it:
http://xkahn.zoned.net/software/zenphoto/patches/zenphoto-1.1.5-bigvideo.patch