Fodor's Travel Talk Forums - West Coast of Portugal

Hello. I am again planning a trip to Portugal (had to cancel last year’s due to illness). I am looking for help on locations to stay and tour recommendations. We fly into Lisbon mid September and then out of Porto end of September. We will not have a car. We are a couple in our mid 70s and in pretty good health (right now!) We will stay in the Sintra area for 6 nights then travel by train (?) up to Porto for another 6 nights. I have these questions below and would greatly appreciate your help!

1. Best way to get to Sintra area from Lisbon airport – Uber?
2. Looking for suggestions on where to stay to visit Sintra and the surrounding area. I have read how busy and touristy Sintra is, so am looking for suggestions of where to stay that would allow us to walk to restaurants, and take an uber to get to the sites we would like to see in Sintra. Would the town of Colares be a good spot? Would somewhere on the coast be too far to visit Sintra? We prefer to stay in apartment rentals vs hotels.
3. In Porto would love opinions on staying in Vila Nova de Gaia vs the Ribeira area?
4. Does anyone have some great tours to suggest? We like wine, hiking, boat cruises and historical sites (will go to at least 3 in Sintra)
Thank you!