Which JKR books should you read before Deathly Hallows?

well I would have to say that you should read book 5 because it tells about the prophecy and everything and also book 6 because it tells about snape and R.A.B who ever he is and about horcruxes and all of those things.It wouldnt be a bad idea to refreh your memory in extras A fantastic beasts and where to find then seeming as it is jkr work. I would read them all again and I have but well I cant wait for the new book and it distracts me I always end up here