When I was debating whether or not to buy a game console, the chance to play Lego Star Wars: The Complete Saga was a significant plus. After finishing Twilight Princess I immediately plunged into Lego Star Wars, and after 20-25 hours of playing time I completed the story portion of the game. If I was motivated, trying to complete the game in free play mode would extend playing time considerably.
It's fun. Easier than I expected due to limitless lives, but over all pretty good. Seeing Chewbacca rip the arms off a stormtrooper for the first time was hilarious. Wha-- did Chewie do what I think he did?! Stomping on 'troopers with an AT-ST is pretty fun, too. :o) The puzzles are for the most part modest, though there were a few that were a pain because I had no idea what to do in order to move on (Hint: on Hoth, straight south and use a mine).
When I try to come up with a comparison all I can think of is Mario in space, and as I've never touched a Mario game take it for what it's worth.
My Mario ignorance may soon be over. After I start and finish Resident Evil 4 (assuming game play doesn't make me dizzy) it's either Mario Kart (assuming I can find a copy) or Okami (which has also received rave reviews). Heck, I'll most likely end up buying both; it's just a question of in which order.