Fryer's Delight for fish and chips, in Theobald's Road.
Ba Shan or Bar Shu for Sichuan or Hunanese in Chinatown - unfortunately there is a spice level, but man are these places good, especially Ba Shan.
Bam-bou for upscale Vietnamese at the bottom of Charlotte Street.
The Cow near Westbourne Grove - sit in the pub downstairs and have oysters with Guiness or kedgeree. (Don't eat in the restaurant upstairs.)
Dock Kitchen near Ladbroke Grove / Kensal Road - fantastic grilled north African / Mediterranean food with a South Asian influence.
The Painted Heron - upscale Indian in a nice corner of Chelsea at the end of Cheyne Walk. Actually truly excellent.
Alounak - superior Persian BYOB in Westbourne Grove, between Notting Hill and Bayswater. They make the flat bread (sangak) in seconds in the concave tandoor oven as you walk in.
Guinea Grill - in Mayfair, a classic old place for steaks and especially steak-and-kidney pies. Might be at the upper end of the price range. I love this restaurant.
St John - if you steer clear of the wine list, I think you could get out of here for under £50 per head - and it's one of the best restaurants in the world if you go to the original Smithfield location. I'm sure you're aware of the style and ambience - if not, google it.