Fuencarral street is one of the main thoroughfares of Madrid, filled with shops and bars. Chueca, on the understand is known as the LGBT-friendly neighborhood of Marid. In my opinion it’s a very colorful and interesting part of town; don’t miss a visit here!
On Calle de Augusto Figueroa, you’ll find the famous Mercado di San Anton: a marvelous covered market. Here you can purchase tapas and other Spanish specialties. On the top floor, there is also a great terrace and restaurant.
Keep in mind that Lateral, one of best tapas restaurants in Madrid is on Fuencarral 43.