I've asked my brother, Andy, in Atlanta to opine. He's a dive instructor and lived in Hawaii for 3 years. I did too but was not a diver at the time. Le'ts see what he comes up with.
Do Molokini Crater, and Coral Gardens. Other very cool non-diving things are Haleakala Nat Park (ride the bicycle down the mountain after watching sunrise on top)
Kauai
Sheraton Caverns (many very large turtles sleep in them) and the General Store. At this time of the year, can’t dive Ni’Iaiau but that is very nice during the summer. Other non-dive must do – the helicopter tour thru Waimea Canyon.
Hawaii (Big Island)
They asked for Maui and Kauai, but the REAL diving is at Kona. Seriously. Do the night dive with manta rays. During day – Coral Dome, Red Hill and the Amphitheater (all close to each other). Non-dive – go to the Parker Ranch in middle of the island (largest private cattle ranch in the United States), then keep driving over to the east (windward) side at Hilo, and go to Volcano’s National Park (still spilling lava into ocean and you can see it). I would go here instead of Maui or Kauai. Also, on the Big Island, you can do a day trip with a shore dive at Kealakua Bay (where Captain Cook was killed by the Hawaiians).
*Photo Upload Requirements:
Please size photos to 800X600 with a resolution of 72dpi for faster performance. Photo upload maximum of 20 per member. Please add a title and discription for all photos and videos. Photos without titles and discriptions will be deleted.