I think it's very important to have dinner as a family (even if you're only 2!) round the table, with plenty of time between courses to discuss things and find out about each family member's day or week. It might not happen so often now but should be at least once a week, probably at the weekend.
It creates a supportive atmosphere, it gives everyone a chance to contribute and it sets an example of friendly behaviour and manners. Chilling out on the sofa is fine once in a while and of course people can talk like that too, but facing each other round a table creates a focal point and brings the family together on an equal footing. The children are included in the conversation, they have the same choice of food, they can feel like a grown up. My two grandchildren sit at the table with us, in their highchairs (16 months old) and they love being with everyone; you can see them picking up the mood and the fun and they always want to eat the same as us!