The main Books for jumping into stories

First Book (HP&SS) - We meet Harry and the rest of the main cast. From here we can go in many directions as we like.

Fourth Book (HPGoF) - I really love this book. Harry has a few adventures under his belt. He is starting to stand on his own two feet without caving to Ron's ideas. We also get to see Harry start to get interested in girls.

I personally hate the rest of the books after the fourth. He's being led around by his nose. Thrown into a trainwreck of a relationship with Ginny. If a girl makes a comment about "How you both look like your parents and meant to be"... Run, hard and fast.

The whole 'Horocrux Hunt's feels like he was cursed/manipulated into it. After Ron ran back to Mommy, Harry and Hermione should have returned to the Muggle world for a base of operations. Not sit around and moan about things...

My two cents...