Hello Jo Carole - thanks for your question. I have indeed driven to Disney several times. With a family of 5, it usually ends up being a more cost effective option.
We tend to play it by ear when we drive. Our ideal time to leave home is around 2:00 a.m. which gets us through the worse part of the trip by day break. On trips when we can leave at 2:00, we'll generally travel about 16 hours the first day, stay a night somewhere and then finish the trip in the morning.
However, if we get antsy and decide to leave the afternoon before we will probably drive 5 or 6 hours, stop overnight, wake up early and finish the drive the next day.
We don't usually decide before hand where we'll stop. Instead, we'll see how we are doing around 5 or 6 p.m. and decide then how much longer we want to go. I then use my handy dandy GPS to look for a Hampton Inn (our preferred hotel stop) that may be coming up for that time frame and make a reservation.
Overall, we don't push it. If you're tired, stop and take a break. A 10 minute restroom/stretch break can do wonders for all.
My fellow panelist, Margaret, is from Illinois. I'm not sure if she has ever driven with her boys but if you happen to be looking for specific tips on driving from Illinois, you may want to send her a direct question.
I hope this helps. If you have any follow-up questions, please let me know. Have a safe trip! Diane :)