For a pleasant drive up to the Alpujarra I normally take people to Pampaneira
You can walk around the village for a while to see the whitewashed houses and flowers in the balconies etc.
Then in the main square there are 2 or 3 restaurants which are good.
There is also a pizza restaurant.
For a very brief introduction to the Alpjujarra click on this linkhttp://granadainfo.com/alpujarra.htm
Most of the villages have restaurants.
A friend of mine recommends the Fragua in Trevelez