Yes, The Dark Knight is a good film.
It's also an emotional wringer. Much of this film is tough to watch.
And it's a film willing and able to go to pretty epic places, story-wise. This is not a "superhero punches supervillain until supervillain stops moving" story; this is a "superhero and supervillain battling for the hearts and minds of the people of the world" story.
Maybe I'll write more fully later. For now, it's been a long day, and wind down I shall.