Within recent years several cult Japanese horrors have been Americanised. The Ring is another, and personally the film I prefered over The Grudge. It was really creepy, and whilst using the unfortunate horror clique of the evil orphan, it is a good horror film with some genuine scares. Certainly having a quality actress like Naomi Watts in the lead role brought added respectability and quality to the film.
But back to The Grudge! It is more Japanese than The Ring. It has Japanese actors and the ghosts are Japanese. I didn't find this film creepy like The Ring, but it does have scare moments that made me jump, and they made me glad I didn't see it at the flicks!! It isn't horror in the gruesome blood splattered type of way many horrors take. It relies heavily on a good story and script. The ghosts themselves aren't scary to look at and yet they are introduced and used in clever ways to provide the scares.