While you may think the dining room table and chairs are the
for this room, they are not. A focal point is a dominant fixture in the room that gives a reference point and helps orient the whole arrangement. You may have a natural one, such as a fireplace, a bay window or sliding glass doors. Or you may need to create one such as a buffet with a large painting above it, or a mural on one wall. Either one could be the focal point if you do not have a dominant feature in the room.
A dining room is primarily used for gathering and entertaining. A table that seats 8 to 12 is optimal. The table should allow those seated a free range of movement. It should not be so large that the inhabits the entire space. If you entertain regularly, you might consider an expandable table. A round table is usually not expandable and to serve 8 to 12 people would require a large table.