Over the years I either watch the full film or skip to my favourite bits. These would be:
Star Wars - none. I always watch the full film.
Empire - Hoth battle + Asteroids (my favourite and most watched scenes in the entire saga)
Jedi - Sarlaac then forward to "It's a trap" and following battles.
Menace - Pod race.
Clones - Asteroids (which are quite poor compared to those in Empire IMO), Execution arena followed by the clones arrival and pursuit of Dooku.
Sith - The opening battle.