Posted much of this elsewhere. Didn't realize there was a special space to review hotels and restaurants. :)
Stay at Hotel el Jardin. HIGHLY recommended. Small rooms and showers that flood the bathroom floor, but clean and neat as a pin. Beds are heavenly comfortable with crisp sheets. Housekeeping staff quiet, efficient and friendly. Front desk staff helpful with bookings, directions, etc. I hated the Ramblas so getting to and from the hotel was not fun, but it is on the quiet Plaza Sant Josep Oriol which goes silent in the evening and has artisan markets on weekends. Get a room with a petite balcony that looks out on the church square, then enjoy the bells. Breakfast included; simple but sufficient. Very inexpensive and a 10% discount for paying cash. RS says you are paying for the location; I disagree. I would have paid more for a different location. But I was happy to pay for the quiet, the clean, and the service.
Eat at El Quatre Gats--historically and architecturally intriguing, good food. The front tapas bar is a different world from fancier the back restaurant; try both. Skip the RS-recommended tapas bars on the Plaza Sant Josep Oriol (Bar del Pi, El Drac de Sant Jordi)--the food was soggy or dried out and service non-existent. His recommendation of La Rita in Eixample needs to be updated: their lunch was 20 Euros, not 11, and service was spotty. My favorite meal was actually the little local bars RS recommends in Barri Gotic--no frills, no English, no other tourists.
See Guitarra Espanola Flamenca, especially if you can get a guitar/flamenco dance combo. Pricey but highly recommended.