I have to say though, that we were in a farther Nemo building once and the closest Cars building once. I found the Cars building more convenient because we had easier access to the parking lot (our car, which we use a lot) AND we didn't have to walk around the pool to get everywhere, and the laundry at the Cars pool was much more convenient to our room than the laundry at the Nemo pool. The main building distance was comparable.
Now, if we had one of the farther out Cars rooms or Lion King rooms, it probably would be better to be in a Nemo room