I just went through the debate you're having. We decided on a minivan.
Reasons:
Minivans are lower to the ground then a Yukon. Kids can easily get in and out. Grandma can get in and out. If you're pregnant, have a broken leg, etc - you're not going to need a step stool to get in your vehicle.
Minivans may not be sexy, but they are set up for families. Power slide doors options, and lift, so when you have hands full you can still easily get the kids in the car.
Minivans generally have better gas mileage. Yukons pull off a whopping 14-15 MPG city. Minvans are 18-20 city. That difference matters.
Minivans also have a slew of other convenience features - like the stow and go seating, makes "pulling the seats out" much less work and when you have the seats up - that means extra storage.
I went with the Town and Country. We bought a 2008 with 22k miles on it. I would have liked an Odyssey, but at this time I couldn't justify the extra 7-10k for the same features to have a Honda. (I went for leather, dual dvd screens, power lifttailgate, hard drive for storing personal music, lots of cup holders, power side doors, rear air, rear camera for reversing, remote start engine, ours also has swivel n go seats which should be fun for long drives)
Hope that helps!
Edit: I saw the first poster. The T&C Touring 2008 second row windows roll down. Only the last panel doesn't - it just opens out on a small angle.