The requirements of your shot (or project) dictates your lighting choices.Your intro states a dimly lit room but your first point mentions the possibility different angles per shot. Whichever you choose, continuity and consistentcy between shots is key. You also may want to get books for lighting and cinematography.

Again, your projects determine your render settings. In the way that you're expecting, you can't leverage speed with quality. To produce good looking animation you'll be using different settings than you would for stills and you'll need motion blur (which take a while to calculate). Specifically, I would set minShadingRate to 1.0, bucket size to whatever your computer can handle - I would enable motoin blur and bump pixel samples up to 9, with a Gaussian filter at 3 pixels. This will give you a look similar to 35mm film.

Have never used the hair room (and not everyone has sucess with it) but I agree that transmapped hair that doesn't move look very good.

I wouldn't do anything which could potentially disrupt the delicate and finicky rendering process. A second computer - a netbook maybe?- is highly recommended.