Preferred difficulty for non-strategy games

[Omanes Alexandrapolites]

Start on Easy although, once I've got the essential grasp, I either up the difficulty to Normal or start a new game on Normal if the former is not possible. I may later move on to hard, but these FPS and similar games seem to follow a fixed almost unchangeable storyline which makes multiple plays quite uninteresting - a bit like watching the same film several times over.