Ok Friday is a week-day.
You need to allow time to clear immigration and customs.
You will then have to face the Lisbon rush hour traffic.
With bags, I would recommend a taxi.
Allow at least 2 to 2,5 hours before planning to catch your train
There is also the Aeroshuttle bus from outside the airport terminal to Gare Oriente.(CARRIS Nº96) - Available everyday, every 30 minutes between 7am and 11pm, the aeroshuttle connects the Airport with Gare Oriente.
You can get tickets at Gare Oriente station. The Ticket offices are on the mezzanine floor. Allow plenty of time to purchase them as the ticket offices may be busy at that time of the morning.
There are two main types of trains running between Porto and Lisbon.
1) Alfa Pendular - High Speed
2) Inter-city - More stops.
If you go to my blog at:
http://barlaventostravelblog.blogspot.com/
Scroll down on the right hand panel until you come to the section entitled:
»» Algarve & Portugal - Travel Transport Links
You will find links to the Portuguese Railways Porto/Lisbon/Faro Train Timetable in pdf fromat which details current services.
Both train types have cafe services with sandwiches and snack on board. I would not try to pick up breakfast en route as the station and airport will be very busy at that time of day.
If the train is not busy, tourist class is fine. There is no smoking in the carriages.
