is a wonderful French bistro across from the Victoria & Albert Museum and nearby the Natural History Museum (itself a must-see IMO). Racine was Restaurant of the Year runner-up a few years back and I make it a point to return on almost every visit as it represents tremendous quality and value. The roast rabbit leg with mustard sauce is making my mouth water as I write this...Moti Mahal
in Convent Garden is an upmarket Indian establishment right in the theater district. I went there myself for the first time a few months ago on the strong recommendation of my boss (himself an Indian). While you could hike over to Brick Lane for an excellent curry, Moti Mahal retains the culinary authenticity in a much more convenient location, with tasteful decor, a wide range of wine and spirits, and attentive service.
While they don't have a website, Four Seasons on the pedestrian-only Gerrard Street in Chinatown (Leicester Square) is famous for their roasted duck. Produce and seafood is extremely fresh, and the wait staff speak English. I will go here myself when back in London next week. Hakkasan mentioned earlier in the thread is a better option for a night on the town (though reservations are tough), while the focus of Four Seasons is moreso on the food itself, and represents a terrific value.