What do you mean Harry Potter will warp my child's mind? I just heard your kid talking about Jersey Shore.
It is often difficult to judge what is appropriate for your child to read,watch, and play at what age. It is always a balancing act and in the end there will ALWAYS be someone who tells you that you are too strict, too lenient., or in my case downright crazy.
My boys are coming up on 10 and 2. My ten year old loves zombie movies, games and books. Now there are a lot of parents who feel that zombies are inappropriate for their 10 year old, that's fine their kid their choice.
Until my kid could grasp the basic concept of real vs make believe (about 4) he was limited to blues clues and elmo. He only watched shows that his reenacting wouldn't cause issues. I was often called crazy and over protective but I felt at 2 and 3 he couldn't yet differentiate between spider man beating up the green goblin and him beating up his best friend. That part of his brain that housed common sense hadn't developed yet.
Over the intervening years what he is allowed to watch has expanded greatly but my basic rules for censoring his screen time varied greatly from that of other parents.
I could care less if he watches a movie with nudity or even consensual sex (not porn mind you I am thinking more like Titanic) my reasoning being that I assume and even hope that one day he will have consensual sexual relationships, but the Simpsons are off limits. This has a lot of people shaking their heads at me but I don't allow TV that glamorizes sexism, racism, and stereotypes.
Killing zombies is ok, that is self defense, killing people for fun is not cool. That is why my kid owns land of the dead but we had a big fight when I told him he couldn't watch Saw even if all his friends had, I don't approve of torture porn.
My kid plays Call of Duty, Gears of War, and Left 4 Dead, I get a lot of shit for that but it doesn't really bother me since I am comfortable with my decisions. there is a legit reason for the killing in those games so I let him play and use them as a teaching opportunity to discuss why it is ok to shoot an invader but not the bully down the road, what makes it different and where our personal line in the sand is drawn. I am still the meanest mother in "all of everywhere" though because I refuse to let him play Grand Theft Auto because it glamorizes a lifestyle I disagree with.
It is a balancing act for every parent trying to find the line between over protective and exposing your child to potentially harmful material