Definitely take the bus to the MK. If you drive, you have to park, walk or take the tram to the TTC, and from there take the ferry or monorail to the MK.
We like to have a car as we travel in late August and it's so hot waiting for the bus when you just want to get back to your resort. We go to the parks early, so our car is always close to the entrance. We also travel to other resort to eat. The downside is that the car is HOT when you get in.
I would have used DME this year because we won't be eating at other resorts, but they pick you up for your return flight so early. Our flight is at 2:30 pm, and if we drive, we can get a good few hours in at the parks before leaving for the airport. With DME, we would have to be back to our hotel so early that it wouldn't even be worth going to the parks.
