The Hotel Dolores Alba, a big pink building set around a central courtyard, has lovely public spaces, like a pretty sun-dappled swimming pool and a patio full of potted plants and birdcages separated only by the distance from the friendly reception desk, where you can buy drinks ($1/liter for water). The bedrooms are a little less airy (this might be because we asked for a room with air-conditioning), but they're quiet and decorated in a low-key manner. They have tiled floors and patterned bedspreads. Our room cost about $35/night; this was in 2002, so prices may have changed.
Breakfast is a buffet of cereal, boiled eggs, fresh fruits, and baked goods - the kind of meal travel-health experts sometimes tell you to avoid, but we ate mammoth quantities from it with nothing but pleasure.
The hotel is located about 3 blocks to the east of the tourist center; I would not have wanted to walk that stretch alone at night, but it seemed safe enough for two people together.
The hotel has parking available.