I have done the Sunrise Safari twice and it is one of the best tours at WDW. You do the ride before the park is open but get to see some of the areas where the animals are kept at night. The ride is done while the animals are being brought out by the keepers and the keepers will talk to you about their animals. The guide is one of the animal keepers and will point out some interesting things about the ride.
I really like this tour and would recommend it to anyone staying at the AKL.