I agree with Jenny-momof3. Love driving and not having to worry about airline charges or changes, security, crowded planes, etc.
We too drive from Ohio every year, although we do stop outside Atlanta overnight. Total costs round trip driving is $400 including gasoline, little food, hotel both ways. Since it is two drivers, we find it best to stop overnight to give our SUV and us a break, check tire pressure and oil, clean truck a little, etc. Stop in to your nearest Cracker Barrel restaurant and pick up
"The Next Exit" book; it is well worth the $15 cost. It tells you what is located at every Interstate exit in the entire United States so you can plan your route accordingly and you will know what is at every exit before you decide if you want to stop. You may also be able to borrow one from your local library.
Interstate 77 south through Columbia then I-95 is the shortest route with two tunnels in West Virginia and Virginia (overnight stop in Columbia). However, we prefer Interstate 75 south through Cincinnati, Kentucky, Tennessee, Georgia (overnight stop outside Atlanta) then Florida to Turnpike. No tunnels.
Have a great trip on whatever you decide. Also, do not forget about Amtrak. You can take your vehicle on the AutoTrain from Lorton, VA or, if you want to go without a car, you could take a regular Amtrak route all the way from PA in to Orlando and it's pretty reasonable for a family.