So, can I help you to narrow down your choices? I'll try. First, how do you want to eat? Spanish, British, ethnic or cosmopolitan.
To take the easiest group first, Sal y Pimienta on the Plaza de las Tres Culturas is a Polish restaurant serving authentic Polish food in generous quantities and at very reasonable prices. We mainly eat there during the winter as our aging stomachs find the food on the heavy side for the warmer weather. Two doors away, a German couple run an excellent pizzeria with an enormous range of pizzas to choose from. Apart from the classics the pizzas are named for local people. Everything is freshly baked, and again, prices are very reasonable. Next, on Calle San Sebastián, the main road through the modern part of the village, you will find an Indian restaurant. We haven't eaten there, but friends who have have offered mixed opinions, so you will have to judge for yourselves. Finally in this category is Al Fuente, on Calle Real, the main street through the historic village.
I'll return to this topic next time.