I didn't start reading the books until after I saw the first movie on its opening day (the film got messed up at the end, so we waited anywhere from five to fifteen minutes waiting for them to fix the projector). I was nine when it came out, so indeed I did grow up with the books. I enjoyed them very much as a kid, that I believe it was the inspiration when I began to really write. I remember when we had to wait three years for Order of Phoenix to be published, that it was around that time I almost lost interest in Harry Potter.
Then the book itself came out, and while it took Mom three days to read it all, I spent about a week or so reading it because it was really dull in the beginning, much like it was with Goblet of Fire. I actually had to re-read it from the beginning because I lost where I left off, and that's when I really started to hate Professor Umbridge. Nasty character, she was.
Movie-wise, the first two will always be my favorites of the series. It really was noticeably different from the third movie-onward due to changing of directors, but I was never particularly fond of them after the fourth movie (again, fifth movie made me squirm because of Umbridge). I have never seen Deathly Hollows parts one and two if only because I just didn't care at that point. By this time, I believe it had been a couple of years since the last book was released. After I finished reading it, I was pretty much done with Harry Potter. I haven't read them again since, so they're gathering dust on my desk. And I also fell away from the fandom at that point as well.
Granted, I wasn't that big of a fan to begin with (even though I was hoping for Hermione and Harry to get together, heh), so I fell away for natural reasons and not because there were crazy Harry Potter fans that ruined it for me. (There was a brief period of time in high school where I occasionally role-played as Hermione--because I look[ed] like a blonde version of her--with a group of friends during lunch, but that was it.) Okay, they kinda have these days, to be frank, but I'm still not interested in coming back to the fandom either way. The last time I read anything Harry Potter-related fan fiction-wise was I think back in June, and it did make me reconsider coming back.
Still, the memories of elementary school being stricken with Harry Potter fever fulfill some of the nostalgic feelings of childhood. I wasn't really that person who was stupidly waiting for my letter to come by owl (it was more-or-less wanting to be a Pokémon trainer, or to be a Card Captor), but I enjoyed the atmosphere as a kid. I don't think I'll ever have similar feelings anymore when it comes to new things in the future, but I do get that urge every now and then to go back and read the books. Who knows when I'll do that, though, so for now, all I have are just the nostalgic feelings, and I'm personally content with it.