There is a Fishworks in central Richmond, it sells fresh fish as well as being a restaurant so you can choose your fish straight from there befor eit is cooked for you. A good range of other dishes as well: crisp fried goujons of sole with aioli; a plate of their own smoked salmon (wild); fresh Dartmouth crab salad with tarragon mayonnaise and cucumber; spaghetti with clams, chilli, garlic and parsley; chargrilled squid with lemon, thyme and garlic or roasted monkfish with lime and sage leaf
http://www.fishworks.co.uk/richmond

Also we like a pub called Inn at the Kew just across from Kew Gardens tube, a great place for Sunday lunch or after a walk in the Botanical Gardens:
http://www.theinnatkewgardens.com/

For a different take on fish, try a Japanese place called Matsuba - fantastic sushi or if you don't like that the prawn tempura bento is very high quality:
http://www.timeout.com/london/restau...iews/8073.html