As a second time visitor I really prefer using my car for visiting parks (we are staying at AS Music), specially this time that we are traveling with a 6mo and 2y childs. But as we also planing to arrive very early in the morning and to stay late in the night (11PM) we also take a mid-day break from noon to 4PM. This time we are considering leaving the car in the park during our break. Is it convinient? How long does it take? we also have 2 strollers: can we leave those in the park?
I would say got the MK the bus would probably be faster as you don't have to deal with the mono or ferry. At the other parks, due all of the variables, it's probably a wash. If s bus is there when you get it might be faster; if you have to wait 20 min for one to show up, it will be slower. Also depends on how far away you are parked; walking or waiting for a tram could add time to the driving option. Can't really help with the stroller question.
Stayed in ASMov with car and I have to recommend always driving. Even with tram and parking (and monorail), it's usually much faster and a lot more comfortable. The bus was always full to the brim and took a few minutes (more than 10 minutes) to arrive. I had a party of two and squeezed in next to the driver but a bigger party would have had to wait for a second bus. And I was there with CL 2 days! We only used it once and decided to car it the rest of the trip. Go for the car. Parking back in the parks after a midday break was not a problem, we rarely got moved much further away. You also are guaranteed a seat in your own car. Go for the car!
Don't you guys have to pay to park?
Or is it free parking at the car parks?
If you stay on site, then parking at the theme parks is free. The parking lots or ramps at DS are free for everyone.
I would highly recommend driving in all directions. If you arrive early then you will not need to take a tram. When you come back later in the afternoon, ask the parking attendants if you can look for a spot up close. We had lots of success with this for our DS1. I liked this strategy because he would easily fall asleep in his car seat and then we'd transfer him back into the room for a nap. (This might be hard if your children don't transfer well though.)
You could theoretically leave the stroller in stroller parking somewhere, but that would be within the park. Meaning you would not be able to take the stroller out through the exit to the bus. And you would not have it at your resort if there is a long walk back to your room. Another benefit of driving is that you can park much closer to your room. Why are you thinking that you'd prefer to take the bus?