In Rome for 4 days in December what part of the city is the best area to stay in - does it matter??? Family of 4 (adult children) able to walk and looking to book an air bnb.
Near Pantheon/ Piazza Navonna/ Campo de’Fiori
You can walk most everywhere from that area
Rome is very walkable and best seen on foot
And I prefer the trendy Trastevere neighborhood. Lots of good traditional restaurant options more so than other areas of Rome. The window shopping is magnificent too. If you don't sleep there do visit and take Rick Steves self-guided walking tour.
Last time in Rome we stayed in the Monti neighborhood and loved it.
I agree with Christine. Just spent a week near Campo de’ Fiori and access to great restaurants in the periphery, easy to get anywhere on foot or an inexpensive taxi ride. We spent Christmas near there in 2011 and loved the festive atmosphere. You might find restaurant ideas here https://community.ricksteves.com/travel-forum/trip-reports/rome-again-restaurants-worth-seeking-out from those we tried recently.