I did my first WiWF tour in January, on day 1 of a 4 day trip, in the noon time slot. I wouldn't schedule it like that again, for a few reasons...
First, it was my first day, and the gates opened at 10am, so I grabbed a small breakfast (like a banana) from the hotel and went to rope drop.... I got to the parks, got my MaxPass, rode 2 attractions, walked around a little, then it was nearly time to check in for the tour. I checked in a little early (like 11:15), then hopped on the train for the whole circuit, and made it back around 11:45. I felt like I was just spending a lot of time watching clocks, when I would typically be letting the "Disney winds" lead me on my first day.
Also, the tour started at 12:00 pm, and we were off and walking at a rather quick clip. Remember the note about the banana I had for breakfast? Well, that 12:00 pm tour has "lunch" somewhere near the 4:00 pm hour, which had me bordering on hangry at the 2:00 pm potty break.
There wasn't anything to make your trip any "better" per se--it's not like they give you touring tips or such. Yes, it's neat to see Walt's apartment, and hear about the Royal Suite, and the petrified tree, and some other tidbits, and hear some things in Walt's own words, but it's not likely to significantly enhance the rest of your trip, at least in my opinion.
As an aside, I wouldn't necessarily recommend the tour for kids. On our tour group, we had an 8yo and 12yo. The family was a group of frequent Disney vacationers who clearly loved Disney, and knew their general Disney factoids and such. However, as interested as the kids were, they were easily distracted, and didn't care much about the stories with the tour. I just kept thinking that their parents paid $85+ per person (assuming an AP/Visa discount) for their kids to be wandering around while the adults were listening. My 14yo daughter is pretty into Disney--both the men behind the Land, and the men behind the company--and even she would have had a hard time with it. It could easily be dependent on the tour guide as well; ours was most interested in chatting up the 20-something couple in the group, and not really connecting with anyone else, which left me, and a few others, feeling like we were missing something. That may color my feelings on if my daughter could have handled it!