We were a family of 4, with 2 small kids. The flat was very big, with everything we needed. The location is great, just 2 minutes' walk from the pedestrian area.
There are plenty of little cafes, where we enjoyed having breakfast. Our favourite was Mercearia do Rosario, in Rua do Rosario, where you get a large breakfast (scrambled eggs, toast, brioche, juice and coffee) for 2 Euros.
The little supermarket across the street is practical for small things, but its choice is limited (no fresh milk).