Currently Being ModeratedNov 27, 2011 11:59 PM (in response to Grampa Doodie)
If you choose the "Full-Original Size" setting, iMovie does not convert your video to the iFrame format because it is already in iFrame format. If you will watch your videos on a computer or a TV use Full-Originl size for best quality. If you will watch it on iphone or youtube than choose 960x540 therefore it will take less time and computer resources to edit your video.
Best iFrame format for your camera iFrame HA1920
Hope Panasonic or Apple will offer an option to use 1920x1080p format because they have much higher quality than iFrame