I wanna take a day or 2 to drive from Orlando and do this trail back to back. Problem is, my wife and kids can't do the distance and they will get bored just waiting for me. So I need to find a nice town with some activities for my family to do while I ride.

I had a similar trip planned to Clearwater. I could go, get a room, leave family at the beach and go ride the Pinellas trail. But wife says that watching 2 children at the beach by herself is a no no and I agree.

So, what town is a good choice to 'park the family' while riding the Withlacoochee?

The trail runs past/thru a very nice small town type park in downtown Inverness. Not Disney World but there are stores and food and perhaps they can make their own entertainment.
Click on this --> http://www.inverness-fl.gov/ and then click on Recreation & Leisure for more details about the parks.

There are a bunch of springs in that area that they can go visit, but make sure you check to see if the heavy rain we have been getting has not made them dirty. Usually takes a day or two to clear them out. With as hot as it has been, the 72 deg water is wonderful.