We want to rent a place to stay for a week in Portugal and do day trips from that point. Does anyone have ideas on a good location?
Dyan
What time of the year are you going? What do you want to see - castles, coast, small towns, cities, wine region?? Your question is a bit open ended and therefore hard to answer.
As Carol says, without more info we can only give you generic advice. But Lisbon is most central with plenty of day trips. Plus a few other major destinations are within a few hours by train or bus. If you're thinking of renting a car though, Lisbon would not be a good spot (though perhaps just outside Lisbon).
Dyan, we found Rick Steves Portugal book to be right-on- the money, and used it to plan a XMass trip in 2007. Pick it us and do some reading, and then determine your interests and where you want to go. We picked up a rental car at one airport and dropped it off in another. We found driving in Portugal to be easy.