You hang around folks of the hoodoo community and you'll hear plenty of talk about The Skeleton Key, with many people even citing it as a favorite film. Personally I didn't like Skeleton Key much, either as a film or for its portrayal of hoodoo. The author of the screenplay, Ehren Kruger, specializes in general horror: he is also responsible for that American remake of Ringu that didn't make any sense plotwise but to his credit was a lot creepier than the Japanese version. The hoodoo of Skeleton Key was pretty much your Hollywood Hoodoo; while the filmmakers went to trouble enough to get a hoodoo consultant for accuracy's sake, the intentions of the spells themselves as written for the film (and around which the whole plot was based) are way beyond what any genuine hoodoo practitioner I've met ever even bothers to seriously try anymore than they attempt spells one sees in a Harry Potter film.
My own favorite hoodoo movie is Eve's Bayou. As of this writing, Wikipedia has a somewhat inaccurate summary that I don't feel like correcting, but I found the general story not only much more interesting than that of its rival, but I also found the portrayal of hoodoo to be much more accurate. No body-switching immortality spells in this one; the means by which the magic finally works are much more alike to the realities of hoodoo. There are (at least) two conjure women in the film. It does include the occasional instruction for a charm: “I want you to get a small bag made of the skin of chamois," one fortune teller advises her client, "In it place this piece of lodestone and John Conqueror root. Tie it with a piece of devil’s shoestring and in your right hand, sprinkle five drops of holy oil. Keep the bag next to your skin.” Eve's Bayou concerns a well-to-do family in 1960s Louisiana, with the main character arguably being a little girl named Eve (although much of the action is driven by the other characters around her.) It was the most financially successful indy film in the year of its premier and received several awards, though no Oscars.