42" - 48" x 60".

From experience--it's not just the table length, it's the position of the table legs. Our 65"-long table has only 43" between the legs, and it's uncomfortable to seat 2 people on the long side. We bought a cheap 30" x 60" table with wider-set legs, 52" between the legs (measured from the inside of each leg). It's quite comfortable to sit 2 on each long side, and one person on each end.

For seating 5 around an oval or round table, I would look for a pedestal base, so that the chairs can be spaced comfortably around the table. Table legs at the outer edge of round tables divide the tables into quadrants, or force one or more people to sit straddling chair legs, several inches away from the table top.

With legs at the corners, you could choose 52 x 52 for added width. We have a pedestal table with leaves. The base splits when adding the leaves. No leg problems.

IMO the table size is often decided by the room size and shape so maybe share that and pics are always a good idea . Just add the pics and any more info in a commnet here do not start another post .I also think how you entertain drives table size . If mostly you do family style dinners then a wider table is nice .

Another important measurement is the size of your chairs. In the kitchen I have a 60" round pedestal table with 6 chairs around the table. These are good sized comfortable chairs and you can just fit 6 of them comfortably around the table. I can squeeze a 7th chair for parties and casual eating.