Harry and Lord Voldemort engage in a "duel" with their wands. During this encounter, Harry's deceased parents appear in ghostly form and give their son advice so that he is able to cut off contact with Voldemort and flee to the Goblet, which takes him back to Hogwarts. Thus, Harry is aided by magic and by the ghosts of dead people.
This duel is power versus power, magic versus magic, but how is Voldemort's magic different from Harry's? It is not; the source is the same. Voldemort is always presented as someone who once was a promising student but went over to the "dark" side. Another movie presents the same concept. In "Star Wars: Episode III," the Sith chancellor tells Anakin, the future villain Darth Vader, that the Sith and the Jedi use the same Force, but the Sith go deeper and use it in a more powerful way. So it is with Voldemort, he is casting spells, but uses his power in a malicious manner, thus making him evil. In the Harry Potter stories, the evil lies not in the use of magic or spells, but in one's intentions.
What is 'good' exactly according to the movie? If Harry is good, then it must be good to use magic for good, since that is what he is doing. In the occult view of magic, power is the ultimate source and magic is neutral; there are no standards of absolute good and evil. Therefore, one's intentions, the results of one's actions, and one's subjective rationalizations for the actions are the measuring rod. But if one bases good on God as absolute good, as taught in His word, then practices such as spirit contact, divination, casting spells, and deception would not be practiced by 'good' characters without remorse and consequences.
This brings us to the crux of the problem with Harry Potter. It is not that the movies or books present occult practices or immoral actions. It is not just that the story endorses these actions for Harry. The issue is what is the nature of good, and how is it defined? If Harry is good, or is doing good, and if these stories are about good versus evil, then what is this 'good' based on? Where and what is the standard for good? Where is the moral absolute? Does it reside in Dumbledore, who is the head of a school that trains students in real occult arts such as astrology, divination, numerology, magical potions, and casting spells? Does good reside in Harry, who has been shown to lack a moral character and who is gaining power through magic? Does the good depend solely on intentions or outcomes, as the Harry Potter storylines suggest? Or does the good depend on magic itself, the neutral power that enables one to practice light or dark magic?
One cannot claim the books or movies teach a moral lesson of good versus evil if no clear picture is presented of what this 'good' is, or if a distorted picture of good is depicted. Nor can one say that magic or one's intentions are the standard for good, when it is God who is the only true standard. Since God condemns occult practices (see Deuteronomy 18:10-14), then these practices can never be good, no matter what one's intentions might be.
My recommendation is that no child under 14 or 15 should see this movie, and ideally that no one should see it at all. The movie is very dark, contains some obscenities, and offers little that is compatible with God's word or with a Christian worldview. In fact, the movie flouts concepts opposed to God's teachings. The few places where morality is given a pat on the head ultimately drown in a sea of paranormal magic and deception.
But due to the gross desensitization in our culture to violence, to darkness, and to the occult, it is more likely that what is shown in this movie will be accepted as "normal." This allows further desensitization, so that the envelope will continue to be pushed just a little more each time, and our children will be exposed to even darker stories and movies until there will be no lines to cross anymore.