We always take that same flight from LA and get in around 6, but we do a couple of park days prior to acclimate. With no time for that, I don't think a hotel room would be worth it. If you're getting in at 7, by the time you deplane, get luggage, check into the hotel and get the kids to sleep (if possible) it will be a couple hours later and you'll have to wake them up after only an hour or two of sleep. If it were me with no other choice, I'd rent a car at the airport, make a leisurely drive to port and let the kids sleep in the car (even park somewhere to get them a longer nap if possible). But we always rent a car anyway because my husband hates the bus. Good luck!