Based on a popular novel by Koji Suzuki, both films are about a mysterious videotape that dooms anyone who sees it to a gruesome but unexplained death exactly a week after. In an attempt to uncover the mystery, a reporter tracks down the tape and, after watching its bizarre content, becomes convinced of its curse. When she discovers her own son has seen it, her fears escalate and she enlists the help of her ex-lover to save her life and that of their son’s. (Along the way, of course, he sees it himself which ultimately becomes his undoing.) Traveling to a far-off island, she finds out the tape’s origins to be connected to a little girl with extra sensory powers (named Sadako in the original and Samara in the remake) who is attacked by her own kin and dropped into a well. Still alive, she focuses her rage before dying, managing to leave a visual imprint that becomes the cursed video. The only way to be spared, the reporter finds out in the end, is to copy the video and to show it to someone else.
Having seen the two films, I find that there are many things to admire as well as nit-pick in both. The Hollywood version, directed by Gore Verbinski, is certainly more glossy, a trait that has disadvantages as it has merits while the Hideo Nakata-helmed original has a gnarly energy that propels the plot steadily forward albeit sacrificing much characterization along the way. The slickness of the remake is certainly more visually impressing but, at a time when pop-music video aesthetics inundate and assault us from the television screens that surround our consumerist lives, it hardly works to set up and orchestrate the shocks invaluable to any good horror film. Every frame seems designed to sell something - whether it be the latent sexuality of Naomi Watts to the latest in home-entertainment technology. The Japanese film isn’t afraid to look "ugly" in parts and doesn’t aspire to anything but scaring the wits out of you.
The point can be further exemplified by the two main passages in the film: the video itself and the climac-tic scene wherein the avenging spirit crawls out of the television set. Verbinski’s video is like a mish-mash of Nine Inch Nail music promos: eye-candy with a lot of dark overtones. (It is wonder why the heroine’s former beau in the remake, played by Martin Henderson, says that the video seems to be the work of students, given the obvious high-production values and flashy CGI-effects.) Nakata’s version is jagged like the product of a genuinely unhinged mind, slow-burning instead of instant retinal satisfaction. The climax, as treated by Verbinski, is full of fast, sharp cuts that interweaves the main footage with shots of Watts racing towards Henderson in a speeding car, presumably to build suspense (or just to get in more close-ups of the admittedly radiant Watts). Nakata is more deliberate in his pace, patiently choreographing the sinister dance between predator and victim to brilliant effect.
However, the Hollywood remake does better in fleshing out its characters. Benefiting from a thoughtful script by Ehren Kruger, the film realizes the drama and interpersonal relationships between the main players that the Japanese version didn’t really seem to care about. Even minor characters like an jovial inn-keeper and the distraught parents of the first victim, a niece of Watts’ reporter, are all given brief "moments" to shine, imbuing the narrative with a humanity that foregrounds the horror. It is of course also a testament to the ability of the actors  most especially Watts  that the viewer is caught up in the situation. It makes you really care about what happens to them. The only sore spot would be the acting of David Dorfman as the son; he comes off like a reject from the casting for another remake of Village of the Damned rather than Haley Joel Osment  which he is clearly trying to emulate.
An aspect that’s interesting is how certain assumptions can be made by watching both films, illuminating some gray areas left murky by the two. It’s almost as if the Hollywood version assumes that you’ve watched the original. One particular plot point is especially intriguing: the question of who exactly fathered Sadako/Samara. In the original, it is revealed that Sadako’s father was not human but rather a beast. The remake sets Samara’s home in a horse ranch where we find her presumed father played by Brian Cox exclaiming after repeated badgering by Watts that he has no daughter nor was his wife "supposed to have children." Also, the main thing we learn about Samara’s mother was that she was fond of horses. The original has a shot in the climax of Sadako’s eye bulging out of its socket  which promptly elicited screams from the audience. The shot of the mad eye is not repeated in the remake’s climax (curious, given that Verbinski chose to quote other shots from the original) but rather shown in another part of the movie. In the scene, it is not Samara’s though: the eye belongs to a horse.
To conclude, I must say that the Ring phenomenon is quite telling. It confirms my suspicion that Hollywood is indeed running out of ideas that it chose to hijack an Asian film to make a good movie. The differences between the two only show the rampant ills of the commercial film industry of the United States, and the lengths it will go to conceal and deny it. However, it must be noted that the two films discussed are both wildly entertaining in their own way. Yes, even the remake. And that seems  at least for now  the bottom line.