For the love of God. Someone wants to avoid the tourist stuff and we recommend Pizza Hut and Wetherspoon's pubs?
Give us a little more info on the museums and places you're likely to visit, but a place that springs to mind is Ciao Bella on Lambs Conduit Street. It's a great Italian, it's not a chain, it's incredibly good value and it's handy for the British Museum.
http://www.ciaobellarestaurant.co.uk/