Honestly...aside from elements of the shining, evil dead, fallen, and clue; it made sense throughout and took some of the ideas of those movies put together while still having its own coherent plot. A decent compilation of ideas and themes. Yes it has Paris Hilton and, no her death is not as satisfying as the one in house of wax, but since she dies early you don't really have to worry about her mucking it up from there on. Not really terrifying, but definately creepy. And the existencialism dialog actually created a pretty good theme throughout as well.
A lot of the reviews talk about how thats not how ghosts and haunted houses work, but really what do movies get right about any theme. If you cared that much about how Hauntings really work, why were you watching a "B" movie about it starring Paris Hilton. You should've known the facts wouldn't be dead on, relaxed and watched it just for pure entertainment, not education.
I'd say that honestly it's not as bad as many of the movies on here if you've got some time to kill. And for a "B" movie, it's really done quite well.