Unfortunately, i came down with something and wasn't able to go this time. But I highly recommend the trail. When I've been in the past, I've started from Elroy, biked to Sparta (about 32 miles, plus a few more miles to downtown Sparta), stayed in a B&B in Sparta, then biked back to the car in Elroy the next day. This time I had planned to go the reverse route, starting in Sparta and staying overnight in Elroy. In retrospect, that plan was a mistake, both because Sparta is farther, and because Sparta is a more interesting town to explore than Elroy. As I recall (and forgive me for being vague), there was a reasonably good steakhouse in Sparta, not too far on the road out of town, past the high school, and a nice sports bar a little further down the road and across the street. There are several places to eat in downtown Sparta, too, but they didn't seem as appealing at the time. Of course, we had no car, so in Sparta we were pretty much llimited to what we could walk or bike to; if your car is there, LaCrosse isn't far and I'm sure has many more offerings.
But definitely do the trail if your family likes biking. If the full 64 mile round trip from the Sparta trail is a bit much for your family, the section between Kendall (where the museum/gift shop is) and Elroy is emminently skippable, and for a shorter ride still, just be sure to go far enough to the experience the Norwalk tunnel (approx. 26 miles round-trip from Sparta, or enter the trail from Norwalk and it's just a few miles - you'll never get a better understanding of the phrase "the light at the end of the tunnel). Bring a flashlight!