This gem of a romantic riverside palace has a superb restaurant which serves both Thai and Mediterranean food. You can sit outside on the terrace next to the river and the pool (where staff will preventively spay your ankles with mosquito repellent) or choose the elegant period Italianate dining room. The Thai selection is varied, and as good as any Thai food I have eaten anywhere in Bangkok, the wine list is small but very well chosen. The prices are reasonable for a place of this quality. I have been three times, and I am going back!
Getting there involves boat rides, which are an added romantic touch. Take the last public boat at sunset and glide by the royal palace as the setting sun hits the roofs and the floodlight s turn on. Get off at Phra Athit, and Praya Palazzo will send their private boat to fetch you. The boat captain will take you back to the public landing after dinner, and will find you a taxi to speed you home. It sounds complicated, but its not.