Any pros/cons...staying Little mermaid room at the AofA.
If you drive to MK, you have to park at the TTC and get the ferry or monorail so it's not as time efficient as the bus.
@missoverexcited is right best to bus to magic kingdom. The rest it is up to you. I tend to take the bus more often than not. Plus my dh And i often split up. I let him have the rental while i go off where and when i want with the busses.
We always do the buses, but I'll give you the con side here. We stayed in a LM room at AoA in October. It is quite a long walk to the bus stop - probably between 10 to 15 minutes. In the mornings, it's not bad, but when you get back and you just want to go to bed, it's like a death march.
Also, since AoA is so large, there are often many, many people waiting at the bus stop at MK and the end of the day. It wasn't unusual for us to have to wait anywhere from 20 minutes to an hour to finally get on a bus -- a packed bus. This is at park closing, of course; maybe if you leave before the park closes it wouldn't be so bad.
I could deal with all of this myself, but my DW said she never wants to stay there again and use the buses.
Using a car keeps you from having to wait on a bus (either at the hotel or park) and it keeps you from having to worry about the next bus being too crowded to fit you and your family.
Parking is free at the parks since you're staying on site, so that is not a factor.
I'd say the biggest pro to using the bus from the hotel to the park is being dropped off as close to the park entrance as possible.
If you're planning to drink alcohol, especially at Epcot, the bus is probably your best bet.