What's your favourite restaurant? Ffiona's on Kensington Church Street. It's really intimate and Ffiona is a friend - she makes delicious homemade pies. It's the kind of place I'd go with someone I really fancied if I didn't want anybody to know.
What advice would you give a tourist? Ask Londoners, and don't stick to the guidebook - you are more likely to find something quirky. I'd tell them to start in Knightsbridge: it's got the shops, taxis, and it's not far from the Natural History Museum and the V&A.