Let's see... I am a grandmother of seven who is obsessed with HP. I wish I could say I read the books because of my grandchildren or even my nephews, but alas, I read them a bit over a year ago after watching the first two movies. I knew from reading LOTR then watching the movies, the books would be better. And I was right.
I have my favourites of course. Though I have a close friend n the boards who will argue this with me, I should let you all know, Sirius Black fell through the Veil and landed in the USA with me. He is very happy here and quite often finds his way into my stories.
I am in Hufflepuff and I am known in there for being the Canon Queen. I have read the books probably over 50 times each with Deathly Hallows being read about twice as much as the others as I always have to read it twice in a row.