I read Harry Potter when I was 9 or 10. I think that's one of the series that taught me not everyone is who they seem to be. By the end of the series, I went from hating one character to really respecting him. As far as the political stuff, I didn't pick up on it. The conflict made sense to me. Maybe if I read it for the first time now I would get it, or maybe even in a reread. It never seemed essential to the story. I get what's being said about the mudbloods and purebloods and all that, but it felt more like nobility verses peasants at the time. And by that, I mean the purebloods held themselves up more like nobility, and lots of them seemed to have family money. Rich VS. Poor. That's a story that continues to be good I think.
I also can't deny the effect it's had on people's lives. I think it's a bit overrated, but it's hooked people into reading books. People who were told they never could. I have a dislexic(I can't spell that) friend who never wanted to read because it was too hard. Then she picked up those books in 5th grade and bam! Also, if what I hear is true, it's kept people from committing suicide, because they've found peace in the world. It's also one of the rare series where the movie adaptations didn't screw it up terribly. So I have deep respect for her in what she accomplished.
Those are the reasons I'm going to reread them. So I can see what effect they may have had on me as a kid, and on others. It didn't feel like there was one at the time, but there's something.