Whilst I like the Potter films I have to say that I would be hard pressed to remember any single line. I've never mentally categorised the films as ones you remember lines from, but as ones you remember action sequences from.
When I remember films like Big Trouble in Little China, Clerks, Aliens, The Fifth Element, The Princess Bride, The Italian Job, Zulu and the like I think of the quotable lines.
But When I think of the Harry Potter films I remember flying cars, Quidditch games, stone chessmen, giant spiders, Deatheaters and so on. They are far more of a visual event for me rather than an audio one.