I would think a 72" round would be about right.

The size we believe will be based on your table-to-wall clearance.

• A child or petite woman, for example, may only require 32 inches to pull out the chair and sit comfortably, without feeling boxed in by a wall behind.
• An average-sized man or woman may be happy with about 36 inches of seating room.
• A husky man, on the other hand, will need at least 44 inches of space.
• Someone in a wheelchair will need 54 inches for proper access and comfort.

Regardless of table shape -- round, oval, rectangular, square or hexagon -- take the measurements from the edges or points closest to surrounding walls.

To allow diners to sit down and get up easily from their seats, try to leave 36-42" between your table and the walls.