If you're looking for a meeting place or a good stop around ½ or halfway between Columbus and Detroit, you can try Bowling Green, OH, which is almost 2 hours north of Columbus, or about 1½ hours southwest of Detroit.
About ⅓ or a third of the way, you can stop at Brush Ridge, OH. This is about 1 hour north of Columbus.
About ⅔ or two thirds of the way, you can stop at Toledo, OH. This is about 2 hours north of Columbus, or a little over 1 hour southwest of Detroit.
About ¾ or three fourths of the way, you can stop at Monroe, MI. This is about 2½ hours north of Columbus, or almost an hour southwest of Detroit.
If you drive straight through without stopping at all, the total distance is 203 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 3 hours, 20 minutes.