Okay, I haven't seen any of the films in this series, not Ringu or Ringu 2 nor Ringu 0 nor the American remakes.
From fans, should I begin with Ringu O and then watch Ringu and Ringu 2? Or should I watch them in release order?
There is no real need to play Ringu 0 first. Ringu (the original) stands alone well, and does not require the prequel to enjoy fully.
Note that Rasen and Ringu 2 conflict each other in the way they continue on after Ringu. They are both sequels, and both pick up right after Ringu.
*** SPOILER WARNING ***
I'm in the middle of watching the saga. So far I've seen:
Ringu - I liked it even though, as horror films go, it's kind of silly. I mean a video tape that is cursed and kills the viewer within a week. There are plenty of bad movie jokes to be pried from that. I will say that while it is silly, it is original. I can say that I have not seen this plot before and they made it interesting.
Rasen - It wasn't terrible but it nearly put me to sleep. I had to make a giant leap of faith to except the goings-on in the first one and this one was almost more than I could take. It's not a bad film but it's overmelodramatic and it kind of steps on what made the first one so original.
Ringu 2 - I liked this one better than the original. Maybe it's the fact that there is so much more going on and the plot gets twistier and twistier. I liked the decision not to have Reiko and Yoichi not killed off between films, even though she doesn't survive the entire film. As I say, this plot is a little screwier and actually reminded me of Nakata's inspiration Poltergeist. Very good film.
Ringu 0 - What a major disappointment. Outside of the original, this is the film I was the one I was looking forward to the most. I always imagine that a prequel is suppose to lay out a base so that we understand the events that would follow. This film didn't explain anything. While I understand that it is suppose to expose the problems that Sadako was having, it never really tells us what we want to know. How did she come back? Who made the videotape? Why did they make the videotape? What are the meaning of the images on the tape? The people crawling along the ground, the guy with a towel over his head? Who filmed all that? This is what I wanted to know.
Next, I'm off to The Ring Virus and then the American remakes.