Don't you think The Dark Knight is overrated?

Whwn you look at imdb's top 250 list , you will see it's the 10th best movie of all time..how is that possible..am I blind , what did I miss?and a lot of people say. Joker is the greatest character of all time..people say that don't watch any movies?I know he acts great(heath leager) but I think it's overrated too..and I m asking that if he didn't die , the movie still great as now? And I think Nolan made better movies such as Prestige(his best I think) , memento and inception (it's overrated too but better than dark knight)