Digital photography

no.
understand how shutter speed effects how your video looks
know what 'auto everything' does to your video and why you should avoid it.
find out what picture styles do to your video and why you shouldn't have jpeg set to contrasty/sharp/saturated as this picture style is put on your video capture.
ask why video downsampled and shown on the web can look gritty with unwanted edge effects (see point above).

You can use any frame rate, shutter speed, picture style, aperture (and so on) you like, iMovie is not going to care weather it is being given NTSC standard def footage shot at f/16 or high def PAL shot in black and white.

That's the point I am trying to make - I am trying to separate the issues for konijn - so he is not trying to resolve his transcoding woes by playing around with picture style or shutter speed.

All your points are valid, but part of a separate conversation.