tayyabs is absolutely awesome, but it's not on brick lane.
the only place i will eat on that street (unless i'm drunk and with other people) is sweet and spicy. it looks like shit but the food is good and cheap.
old stand-bys are viet hoa on kingsland road for great vietnamese food, tre viet on mare street for the same but better.
mangal ocakbasi on arcola street in hackney for the best turkish barbecue outside of turkey. also any number of places on green lanes.
the eagle on farrindon road for gastropub business, but there are plenty more to try.
if you want a really good, mid/lower end of expensive dinner try moro on exmouth market for excellent vaguely middle-eastern-accented mediterrannean food. it's my favourite place to eat in london, period.
frocks on lauriston road, right near victoria park, for lovely and really reasonably priced french/english bistro-style cuisine (and a killer cheesecake dessert).
pretty much any jamaican joint in brixton or east london is worth a go, too.
then there's glas in islington (i've never been here, but i have been to it when it was located near borough market). gorgeous scandinavian food. they do a kind of tapas-style tasting menu where you order about 6 things between two people, it's great summer food with chilled vodka or good white wine.
eat around borough market, too. there are tons of places around the market that do good things. one does a wicked merguez sandwich.
it's total nonsense that london has bad food. it never has, actually. it's one of the best eating cities in the world. you just need to know where you're going. anyone who eats badly is a tourist who hasn't done their research. if you're staying in central london and visiting chain restaurants, you will get shit food and it will be expensive. if you're prepared to travel a little and are willing to be adventurous you'll eat very, very well and it won't break the bank.
if you're really fucked, just head into a greasy spoon cafe and get a cup of tea and a bacon sandwich. it's our culture, after all...