Here's the deal, I think Ringworld is actually pretty boring. I used to think it was the cat's pajamas, but it turned out I was really more fascinated with the concept of the Ringworld itself then I was about the story. Louis Wu & Friends on a road trip... it's ok.
Here's the Niven stuff I'd really like to see on the big screen:
1. The Mote in God's Eye
2. Footfall
3. Lucifer's Hammer
Notice a trend? These are all books he co-wrote w/ Jerry Pournelle. With few exceptions both Pournelle and Niven have serious flaws when writing alone. But when they write as a team, wonderful things happen.
Imagine the USS Archangel Michael at the end of Footfall, now THAT would be an astonishing bit of film. I can replay that battle in my head at will, years after reading the book. Or the Lenin in Mote engaging the Macarthur after its... 'capture', and trying to pump enough energy into the shields to get a breakthrough. Or Harry Red on his Harley ride across the broken remains of the USA after the comet impact, hooking up w/ what's left of civilization.
These are film moments for sure.
(PS, there are a couple of Niven books that might be good alone, but not many: Protector is one, Man/Kzin stuff might be another)
