I voted Ep. 1 for the Maul/Qui-Gon,Obi Wan sequence. I think the best death overall was Obi Wan slicing DM in two, but I agree you really were not expecting Qui-Gon to die so there was shock. In ROTS you knew all but Yoda and Obi Wan were going one way or another. Mace going down was a close second. If we didn't all know he was getting it, there would be a hell of a lot more shock value to it. For this reason, when I share the SW Saga with my kids it will be in order from 1 to 6.