We've gotten a lot of playing time out of Lego Star Wars II: The Original Trilogy. It is so far superior to the first LSW that we were able to rent LSW1 and play through all the story bits in one weekend. But LSW2 is much more robust.
In an advertisement for LSW2, the narrator spoke of playing your favorite characters from the OT: "Luke Skywalker, Han Solo, Princess Leia, Darth... 3-PO?!?" The boys have used the "design a character" feature and are now both running around Dagobah as Darth 3-PO.