While owning most of the games, I fail in the category of owning all of the books. I've just read them as taking one out of the library is a lot cheaper than getting a brand new one. I think lore wise though I'm pretty good for it, know the majority of extra lore and all of the major events throughout.
I picked option 5, but I can name several quotes from the games and I have owned all of them except for Halo Wars and Halo Wars 2. I don't own any of the books but I am hoping to get them soon! I also know quite a bit of the lore.
I picked Option 5. I love the lore and backstory of the Halo series but I mostly play for fun! Every now and then, I'll read one of the books or research the history of an alien race but other than that, I love Halo for it's fun factor.
I loved Halo when it first came out. Playing Halo CE back in high school and I knew it was something special. However I didn't really dive into the lore back then. But my friend and I have been playing through every campaign coop starting with CE, and as soon as we finished Reach, I was hooked. I'm reading the fall of reach now, and am learning everything I can about the universe. Love it.