Braga is Awsome and Estoril is very cool too (used to be a F1 track). Although i haven't been there everyone says that AIA , the new international circuit of Algarve, is by far the best one.

The thing is that they aren't open to the public except in organized events. For you to be able to drive in them you have to be in a trackday that usualy happens once or twice every month.

Let me know when you come and i can try to find something for you.