Is it safe for 2 women to arrive at Rome Fiumicino FCO at 20:45 on a Thursday and take the train/metro to central Rome lodging?
Joan, Even at 20:45, I doubt that you would have any trouble as there will still be lots of people around. Travel by Taxi or via Leonardo Express will likely be about the same cost. Tickets for the LE are €14 if purchased from the automated Kiosks. Depending on where your "central Rome lodging" is located you may or may not have to use a Taxi from Termini. I usually take a Taxi from Termini when first arriving, as it's a lot easier with luggage. Happy travels!
Probably but take a taxi, far easier than taking the train and then shifting to a car. The car rate is fixed at 4O and something higher for night so it is about the same as the train and cab.