As a tank you should be wall to wall pulling in order to stay ahead of dps or healers in almost every dungeon past level 50. If they feel the need to pull for you, then you are going too slow.

When it comes to watching cutscenes I'll usually wait for them to finish except for the select few that over several minutes long-like Stone Vigil and Toto-Rak's. There is no reason for any cutscene in an instance to last longer than 10 seconds. If the cutscene is longer than that, I will pull instantly.