Many thanks to all the posters who provided the info we used for our research. We came to Kauai for the first time mid-February and stayed at a VRBO place near Anahola, for reference. I would not do this again, as we don't mind driving around to do things during the day, but for dinner we found we strongly prefer a SHORT drive, or better yet, a walk to and from the restaurant. Therefore, we would stay closer to where the nicer restaurants are and travel more for our day trips, if necessary, rather than the other way around. Lesson learned. We actually moved for part of our trip down to Poipu which made our dining much more pleasurable.
General observations: I believe it is possible to find some fairly good food here and we enjoyed many meals, but it is really difficult to find a good cocktail. Admittedly, we are picky and we live in Portland, OR so we are spoiled, but many of the non-tropical drinks we tried were extremely poorly made. Best to stick with beer/wine if you are particular, or maybe the tropical cocktails. Also, although the island is small and you can drive a lot of it easily for day trips, it can take as much as 40 minutes or more from Kapaa to Poipu because of the traffic. Going north from Kapaa area has much less traffic, but I think the food in general is better in Poipu.
Sat at the bar, which we often prefer to dining at a table (just our preference). Had the miso soup (just fair), the ahi wrap (the best dish with nice flavors), and the burger (also just OK). Tried their Mai Tai, which was just OK and then switched to beer.
Roy's Tavern (Princeville):
Had a nice view overlooking the course at a table in the bar area. Had macadamia flatbread, which we enjoyed, the salmon salad (very good), fried chicken (just an OK version), and ahi poke (very good). As for drinks, I ordered a Tanqueray & Tonic, which suffered from the pitfall of mixers coming from a gun, but was reasonably strong.
Anahola Farmers Market:
We had the combo chicken and pork plate from the farmers market. Expensive for take out, but you get a ton of food. We only got one combo plate and it was enough for dinner and lunch the next day (around $18, I think). The chicken was better than the pork for me.
Ono Family (Kapaa):
Had breakfast here. Both of us had some variation of pork with fried rice and egg. Large portions and reasonably tasty. I had my egg sunny side up and the white needed to be cooked a little more for my taste.
Tiki Tacos (Kapaa):
Loved this place. Lots of choices. We only had one (huge) taco each: a kahuna fish and kahlua pig. Both were excellent. Tacos run about $8 each.
Beach House (Poipu):
We actually ended up having one dinner here (impromptu, in the bar facing the ocean and the sunset) and one lunch (with a friend in the area who wanted to take us there, as it is here favorite restaurant in Poipu). For dinner, if you want to enjoy the sunset, you need to have a reservation or get there early. We arrived probably shortly after 5 pm and easily got a seat in the bar area with an excellent view. Shortly after that it filled up considerably. We shared the crab stuffed ahi appetizer (pretty good, but not special) and a beet salad (this was quite good). Our main dishes were the miso encrusted fish and fish in red curry sauce. Both were very good. I enjoyed my red curry dish, but it could have been a touch less sweet. The miso dish was decidedly more savory. To drink I think we stuck with a beer for appetizers and then some champagne with dinner (it was a special occasion).
The lunch we had there consisted of fish tacos for both of us, which we really enjoyed. I also had some sort of tropical drink (the Majestic Mai Tai) which was good and quite strong.
Red Salt (Poipu):
Sat at the bar on one of the nights they have a sushi chef at the bar. The dining room was VERY busy and the single bartender was slammed, therefore our service when we first sat down was extremely spotty in the beginning, but improved substantially once the dinner service settled in. Opted for gyozo appetizers then a variety of sushi made by the guy at the other end of the counter. Overall we enjoyed the sushi very much. Can not comment on the entrees there as we did not try any. We had a small bottle of sake; they should have a larger selection given that they have a sushi chef there at least 3 nights/week. It would have been more entertaining to sit at the sushi end of the bar as well, to watch the preparation (right hand side as you look at the bar).
We had one lunch at the poolside bar one day. We each had a burger and fries and it was a pretty good burger. Had one of their signature cocktails from their list (The Spiked Tea), which was vile and we only had a couple of sips each, then left the rest.
We also had breakfast at the Red Salt, which was included if you stayed at the resort. It was a decent buffet of fruit, cheese, salumi, oatmeal, cold cereal, yogurt, some muffins and breads. Also, there was an a la carte menu. We had banana pancakes (good), breakfast burrito (OK).
Living Food Market (Poipu):
This is an upscale market for grocery shopping (the meat and fish appeared to be of good quality) and prepared food (deli food, sandwiches, pizzas). We got a deli sandwich one day which was reasonably good. If you are staying in the area and want good quality proteins, this may be the place to go.
Ahh, Merriman's. We are huge fans of the Merriman's on Maui, so we were excited to try this one out. The location is not nearly as nice as the one on Maui, but it is a solid option for food. Definitely our favorite for food on the island. We only ate in the upstairs restaurant (they have a more casual place downstairs that has a completely different menu). We sat at the bar 2 nights and at a table for a third night. We love the Kahlua Pig Quesadillas at the Maui restaurant and they are still good at the Poipu restaurant, but somehow they were just a tad different and we did not enjoy them as much as we have in Maui. We also tried the poke sampler and I fell in love with the ono poke. There were 3 on the plate for the sampler or you can order them individually; ahi, ono, and keahole lobster with avocado. They were all good, but the ono....! For mains we had a chicken dish and a lamb dish, both of which were very good. On the subsequent nights, we had the full portion of ono poke (skipped the sampler), the crab cakes (sorry, can't remember these), broccoli side dish, sweet corn side (reminiscent of creamed corn but without the guilt of eating something from can), and the wok seared ahi entree, which I liked well enough to get twice. We also had the macadamia nut crusted fish for an entree one night, which my partner enjoyed.
For drinks, same problem as other establishments. They focus on tropical drinks, which is understandable, but we generally find them to be too sweet for our tastes. We do enjoy what we call the "short" Mai Tai at the Merriman's on Maui, nice and strong, not too sweet, but the bar menu is different at Merriman's Poipu and we did not enjoy the Mai Tai as well. I made the mistake of ordering a Manhattan one night and also I specified to the bartender that I wanted it 2 oz bourbon to 1 oz sweet vermouth. She free-poured (ie did not measure to ensure proper proportions) a ginormous version of the drink then proceeded to shake the heck out of it (instead of stirring) for a really long time, which produced a very watered down effect. Sigh. I know I am overly picky.
All in all, there are good things to be found on Kauai. Depends on your tastes, preferences, palate, etc. We would stay in Poipu again for the food choices and travel elsewhere for activities but we tend to emphasize food on trips and this may not suit all travelers.