You can drop them off at CityWalk, I think where the buses are. I know I have seen signs for the drop off lane. It's outside the parking garages. Where the taxis are too.
You can also drop the off at a hotel, the Hard Rock is the closest.
There is no free parking to enjoy the restaurants or bars at the hotels. Parking is more expensive at the hotel than at CityWalk. Note, after 6pm, you can park in the 2 parking garages at CityWalk for free.
The walk from the Hard Rock is about 10 minutes, and the line through security tends to be not that long. From CityWalk, it's about a 15 minute walk, and going through security can be crazy.
Either way, dropping them off early makes life easier for all.