Right OKAY, by far the Hardest of the 3 to date, simply because there are so many changes and things in the books which never made it to the movies and that makes me sad. So what if the movies had been 6 hours each, in fact bring it on ha.
So after having a long, hard think about it I’m going to go with the scenes from the Quidditch World Cup which starts off The Goblet of Fire which is the fourth book/movie in the series. In the book we have our first magical event, outside of Hogwarts and it was spectacular. For me it set up/explained a few things that are important to the rest of the story.
Veelas the magical and beautiful girls who had powers to seduce men and who turned into dangerous, bird like creatures when angry.
Winky the House Elf and S.P.E.W, Poor Winky who had been freed from Barty Crouch and then employed by Hogwarts. When Hermione discovered the work the House Elves do for the great feast and in general for Hogwarts she sets up Society for the Promotion of Elfish Welfare.
Charlie Weasley poor lad, in the book he appeared a lot for looking after the dragons for the first task, unfortunately he didn’t make the cut into the film at all.
Hermione’s frizzy hair and buck teeth that she tried to fix for the yule ball, all we see in the film is her appearing looking beautiful and elegant without all the preparation she went through in the book.