Fodor's Travel Talk Forums - 3 weeks in Portugal

Greetings, all -

My husband and I are planning a 3 week trip to Portugal for late October-early November. We are frequent travelers to France and Italy, but this will be our first visit to Portugal. I've been reading the forums and guidebooks and our itinerary is pretty well set.

We're spending a few days in Lisbon, then picking up a car (at the airport, per recommendations here) and driving to Evora and Estremoz for about 4-5 nights. We'll return the car to the airport and then take the AP or IC train from Santa Apolonia station to Coimbra-B for 3 nights. Train again from Coimbra-B to Porto Companha and after several days in Porto take the AP train back to Lisbon for a few more days in a different neighborhood before we fly home.

I have some specific questions that I'm hoping experts here can answer to assist with!

My husband is now 65, so qualifies for the senior discount on his train tickets. My friend (joining us for part of the trip) and I are not quite there yet, so will be looking for non-senior promo fares. Will I need to book these tickets as 2 separate transactions on the https://www.cp.pt site?
Am I correct that sitting on the left/coastal side of the train heading north and the right/coastal side heading south will afford the best views?
We like to walk and are accustomed to the hills of San Franciso, but not the slippery mosiac sidewalks of Lisbon. I saw Maribel mention here that she has special Portoguese walking shoes and would love recommendations for a woman's shoe with arch support that is not too bulky looking.

Many thanks in advance.