For my recent trip to Barcelona I booked in at Hotel Ingles, which is on the Carrer de la Boqueria, about 30 seconds walk from La Rambla.
The hotel staff were friendly, I had a single room with an ensuite shower room. The room was cleaned and tidied daily.
Breakfast was included in the stay, and for that you nip to the bar nextdoor and hand in a token in exchange for coffee, orange juice and 2 slices of toast or coffee, orange juice and a croissant.
I would recommend this hotel to anyone who is on a budget or is more interested in exploring Barcelona than staying in the lap of luxury. It is ideally located, the street its on is near lots of bars and restaurants - including the restaurant Can Culleretes which is very popular and less than a minute away!