I feel that I should write up what I did for future reference.
We went to the Oriental Sala Rim Naan the first night as we had just gotten of a flight from the NYC-SIN-BKK, and after 18.5 hours in a plane plus the time to BKK, we were exhausted. Additionally, we thought our two young girls would love the show (which they did). Food was good - more western - but not by any standards the best we had.
We tried Ban Klang Nam (the place written up in CN Traveler for Jan). Didn't love it although some of the food was good.
We went to Celadon twice. The first time the food was excellent, but the service was terrible (we compared it to the flight over on SIA, but said they couldn't even fulfill what the FAs had done!). We went back again, and service was much better. Overall, this was our favorite restaurant in BKK, not the least because of its varied menu (and high quality, of course). I believe dinner for five (essentially 3 adults/2 children) was around 100USD, quite affordable for most westerners.
We went to Thiptara. We enjoyed this very much. Food was very good and service was excellent. Felt about the same for Baan Khanita, although it was much more lively .
We had breakfast at the Oriental everyday. Buffet was not wonderful so we mostly ordered a la carte which was very nice. We found service geniuine, efficient, and friendly; we loved the aspect of being out on the river, especially before it got too hot.
We also had tea in the author's lounge a couple of times. Great experience - service, atmosphere, and music. I recommend it to anyone going to Bangkok.
Overall, in Thailand, our best meals were those in the FS Chiang Mai. The food here was phenomenal (contrary to some things I heard hear and in the Luxury Hotels forum). The food was the most creative, and of the highest quality. Much of the menu had northern influences in it (being that it is in the north), which we enjoyed. Breakfast at this resort is phenomenal (it is western), and not to be missed. BTW, this is a phenomenal resort. We were there for a good portion of our trip and loved it. Chiang Mai is not really worth going into much. The night bazaar is nothing exciting and the temples in CM are worse than those in BKK.
Amanpuri, Phuket also had excellent food. If you go, make sure to get the set menu. I'm not sure what breakfast is, however, as we had room service delivered to the villa (actually, all of our meals but one were in the villa). One thing we enjoyed here, too, is that some of their food is regional; additionally, they are willing to make whatever you want for you.
OT, but in SIN, I recommend the Chinese restaurant in the FS (on Orchard Blvd). It was phenomenal - best Chinese food I have ever had. One thing to note is that on Sat/Sun, they have a special menu of 100 items that you can order as much of as you want (including a boal of shark's fin soup) for a set price of around 45 SD. It is a great value. Add unlimited Veuve Cliquot for only around 50SD. I wholeheartedly recommend this place to anyone in SIN.