there are no best graphic settings. high video settings might distract some people, especially shadows. these can be very annoying in 'russian revolution' mission.
depends on your preferences. if you have wooden pc you turn everything down, if your pc is good you set all these to high. there is no pattern. personally i would play on highest settings if my pc would allow me to do so, because game looks way better.
as long as your fps is above 60 and you have no lags it doesn't really matter i think. one thing i would turn off is vertical sync. just do some tests and find out what is the best for you.
I remember many years ago viewing the beginning of a highlighted run which started just as the previous attempt was coming to a semi-disastrous close. Sometimes a VOD like this was accompanied by a remark signaling frustration or lost hope which, I suppose, the runner felt was a bit of amusing juxta
