I last year got box of Ringu 1, 2 & 0. I think I've first Ring.
This original (actually there is a TV version before even this) is great. Ringu 2 was disappointing. Ringu 0: Birthday is rather different, but I liked it better than 2.
Ring movies are an unbelievable mess. I once tried to make sense of them I'll copy my old post from elsewhere. (Note that here I'm referring Ringu as "Ring" and American ones as "The Ring").
Here's all the Ring films:
- Ring: Kanzenban is a TV movie based on the original book
- Ring is movie based on the book, followed by sequel Ring 2 and prequel Ring 0: Birthday which is partially based on 4th book (that is a short story anthology, unlike other books)
- Ring aka The Ring Virus is Korean film supposedly based on the book, but taking elements from Japanese Ring movie
- American film The Ring is based on the Japanese Ring movie, followed by sequel The Ring 2 (and "Rings", short film DVD extra set between 1&2) and upcoming Rings (previously known as The Ring 3D)
- Rasen(=Spiral) is Japanese film based on 2nd book "Spiral"; it does not fit in same continuity as Ring 1/2/0
- Sadako 3D is a sequel to Rasen, based on 5th book "S"; it was followed by sequel Sadako 3D 2
- coming up this summer, Sadako vs. Kayako is crossover of Ring and Ju-on aka Grudge
