Hi!
If you don't have a car, you probably don't need to rent one. You can park it for a short time (15 min?) outside the meadows trading post, but not near the restaurant (trails end) or boats to MK.
When you stay at the cabins you need to take an internal FW bus to either end of the campground (Settlement or OUtpost) to catch another bus or boat to the parks. Settlement has the MK boat & I think the MGM bus. Settlement also has a store, restaurant, bar, petting farm. Outpost has the Epcot bus and trail rides. They will give you the info at check in.
For complete info on transportation, read this thread
Ft wilderness transportation
There is also the meadows area, near the middle of the campground. THis is where the nightly campfire is held. There is a pool & store here.
There is another small pool near the 2500 & 2600 loops (all cabins). You can walk there from either of these loops.
I loved the cabin, but feel that a golf cart would make it easier to get around. We didn't have one. It's also nice to have a car for groceries, since you have a full kitchen. If you taking a town car from the airport & doing a grocery stop, be sure to have a complete list ahead of time!
If you are comparing a cabin to 2 rooms, the downsides are
- 1 sink & it's in the bathroom
- 1 TV in the living room
Have fun deciding!