Have the biryani at Bawarchi (near RTC crossroads)
For a perfect Nizam-style biryani lunch, try Madina Hotel (in Patterghatti).
For breakfast, head to Pragati Gully in the alleys of Sultan Bazaar (Koti area).
Malgudi (Begumpet) serves food from the four south Indian states, including some dishes that can't be found in any other restaurant.
The interiors of Ohri's Serengeti (Banjara Hills) have been designed to resemble a jungle but the food is not African. They serve Peshawari and Lucknowi cuisine, and have a good wine list as well.
Designed like a dhaba Angeethi (Banjara Hills), also has a paan (betel leaf with spices) shop, a well, and a "quack" selling herbal remedies for "marital problems". Give the medicines a pass and try the Indian food instead.
So, in Jubilee Hills, is a pretty restaurant with open rooftop terrace seating - perfect for a romantic dinner.
For good Italian food, go to Via Milano (Italian) in Jubilee Hills.
Try Urban Asia (serving Thai and Chinese cuisines) in Jubilee Hills.
Zafraan Exotica, serving Indian food, has great ambience, with woodwork, an artificial waterfall with pebbles, and candle-lit tables.
Peperoncino is an Italian restaurant with an open terrace and spacious inner seating.
Khaan Saab serves excellent Indian non-vegetarian food. Try their tundey kebabs and burani paratha.