Not sure where in NJ you are starting from, but I am about an hour and ten minutes from DE, as reference. I leave early, 2:30AM and go straight through, arriving in the WDW area by 6:30 pm or so, depending on stops, traffic, weather, etc. I think it has been as early as 5:30 PM and as late as 8:30 PM. Everyone else sleeps for the start of the trip, and it may be NC or even SC before they awaken! I can't handle overnight drives, and get up early for work anyway, so rising a couple of hours earlier and leaving works best for me.
I think the first time driving down we did leave later and stayed in the Jacksonville area. And other times we spent the first night in Winter Park or Altamonte Springs, but now go to Orlando itself, then check in at WDW the next morning.
Also we have stopped sometimes on the way home, as no one but me wants to leave WDW 2:30 AM, and stopped in VA (usually the Emporia area, or a little further north). But sometimes we are making good time (hitting that usual stopping area at say 6:30 PM) and made it home a little after midnight after having left WDW 8 AM.
Check the cancellation policies for any hotels you book. A couple of the major chains started requiring 24 hour advanced cancellation to avoid charges (up till 11:59 PM the day before check-in), instead of allowing you to cancel up till 6PM the day of check-in.