I have not stopped in Vila do Conde (I did the Central route but passed by Vilar and went on), but dishes with Bacalhau (codfish) tend to be great.
If you have never been to Porto, I would highly recommend a day there as well. Try Bacalhau a Gomes de Sá (codfish in the oven with olives and boiled eggs), Francesinha (2-cheese, 7-meats sandwich with beer gravy) and Port wine!
EDIT:
In Ponte de Lima, we ate in one of the restaurants in front of the river. Cant remember the name, but was he one that did NOT look fancy. It was delicious.
In Valença do Minho, there was a restaurant inside the fortress that was fantastic. Not so cheap as menu del dia, but worth it.
In Caldas de Reis there is an old, oooolllddd tavern in front of a spa that makes pimientos de padrón and also crispy fried sardines that were to die for. And portions were HUGE.
Although I can´t remember names of places (sorry), the camino portugues was one of the best gastronomic experiences of my life