Most Anger Inducing Scene
Ohhh there are so many of these! From all scenes including Voldemort, to Snape's frustrating behaviour, to Umbridge's abuse of power, Rita Skeeter and her poisonous quill, Fudge and his derpy derp behaviour - I don't even know where to start?! I think I'm going to go with;
Harry's Mistreatment by the Ministry of Magic
Everything about this pissed me off. From ignoring his warnings about Dementors, refusing to accept that Voldemort was back, trying to get Harry out of Hogwarts in every single way possible. Oh my GOD I wanted to smack Fudge silly! Frustrating, silly, naive little man. I totally understand that he didn't want to believe that ol Voldy was back but come on! Think of all the trouble he could have prevented?! Don't even get me started on what happened to Sirius. *Fumes*.