The woman in black is a fucking bitch. Seriously she just keeps killing kids for almost no reason, and even after her son is brought to rest she doesn't stop, though she does pretend to just to troll everyone. With a soulless villain like that you have the beginnings of a decent film. What makes this a decent film is firstly it wasn't made in the Noughties, which produced very few to non decent horror films, and secondly it tries to evoke a more gothic type of horror, which can be very effective when coupled with a decent director and actors, and besides Daniel Radcliffe they are.
Now with Harry Potter as the lead actor it is a little bit strange, but it works alright after maybe 10 or 15 minutes, you even sort of forget that Daniel is the lead actor. As a character he is kind of a blank slate, but he does have a driving motivation of his son, so he has like maybe 2-dimensions, which is not bad for a horror protagonist. Our villain is a fairly standard ghost, bringing back other ghosts, though they don't seem to affect anything physically, just mentally scarring the townsfolk. The people themselves are standard cliches, fearful of foreigners and ominous about the location of the film.
The location of the film is great for a horror film, a mansion in the middle of nowhere, with rolling banks of fog, a path which disappears when it is convenient to the plot, and even a dark forest if you need that. The house itself is a great example of a Victorian haunted mansion, with lots of candles, hallways, staircases, and creepy children's bedrooms. Apparently the toys of the era where absolutely terrifying, with the whole range of creepy, clowns, monkeys, the blank stares of dolls, and good old fashioned self rocking chairs. The whole gamut really.
The main question of any horror film is of course is it scary, which I can answer with a resounding probably. It's got some good images, a fairly scary lady ghost, and a good amount of creepy children, with a array of different murder methods. There is also a good sense of desolation with Harry being the sole person in the house for much of the film, including just about all of the actual horror stuff. There are a few cheap jump scares, but overall it is mostly atmosphere, and fairly well done at that. Admittadely they could have done more with the environment, and probably should have given its roots, but you take what you can get.
There are a few things that don't work, such as the downer ending not really making too much sense. They could have had a nice simple ending, ghost defeated and all that, but no it is a horror film so has to have a shocking ending. Also they forget about the dog that was in the house which was kind of weird. They made a point to include it, then just kind of, forgot. Also Harry's acting is a little bit okay, I mean he's never been great, and it's on show here as he has to do a good 80% of the acting. Overall though it's a decent horror, with a few scares, and an actual decent finale, an issue that many horrors have a lot of trouble with.