I just remembered another one: Serenity is another sci fi movie that came out in 2005. And Joss Whedon even had the main character shoot someone who was unarmed partly in response to the Greedo scene. I'm a huge fan of Buffy but I thought that movie was only ok.

Would the prequels have done well if they weren't Star Wars? Well, they didn't have a substantial drop off (week by week in ticket sales) so word of mouth must not have been too bad. I hate that I'm sounding like Rick McCallum (he did say something to that effect) but I honestly believe that if Matrix and Pirates could get sequels, non star wars Phantom Menace would have done well on its own. It would have been unique enough that plenty of people would have come even if out of curiosity.