<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by YYZ:
The concerns are whether we would be able to fit a day trip to the volcanoes, and whether there would be enough places to eat without being stranded on the resort.
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You certainly will have enough time for a day trip to Volcanoes National Park. It won't matter which resort you're staying at because all are, like other posters have said, near each other. Have you considered spending a night at one of the lodges there? There's two. One's Kilauea Lodge and I don't know the name of the other, but this would allow you to bypass a night drive around the island.
Drive time, Kailua-Kona to Hawaii Volcanoes National Park: 2 hours, so tack on another 30-45 minutes or so from the resort to Kona and you have roughly about a 2 1/2 hour drive.