The official address listed for Ft Wilderness Resort is 4510 Fort Wilderness Trail, Lake Buena Vista, FL 32830
If you're coming north on World Drive, go to the MK tollbooths and stop at a tollbooth far to the right. Tell the attendant you're going to Ft Wilderness and s/he will let you thru (no charge). Just past the tollbooth, follow the exit road on the far right (continuation of World Dr) and there will be an immediate fork in the road. Head right at the fork and you will be on Vista Blvd. Stay on (mile or so) until you see Ft Wilderness entrance on the left. Turn in, tell booth attendant your plans, and s/he will point you to main lot just ahead to the right. Park and get on a Ft Wilderness internal bus to The Meadows Trading Post (Chip and Dale Campfire Singalong). Bus drivers are friendly and if you're worried about getting on the wrong bus, they'll make sure you're on the right one.
It sounds like a lot, but it's really a cinch. Plan to be at the FtW internal bus by 6:15.
Another way to get there is a boat from MK, or a smaller launch boat from the Contemporary or Wilderness Lodge. Take either boat to Ft Wilderness. At the FtW dock, walk up a path and you'll be at a different Ft Wilderness bus loop where, again, you can get assistance getting on the correct bus to The Meadows.
To exit the way you came, follow FtW exit signs and turn right (west) onto Vista Blvd. At the forked intersection, go right (north) onto World Dr. Get into the left lane, because you will turn left at the next intersection at Seven Seas Drive. Pass the TTC, pass Poly resort, come to a "T" intersection where you will turn left (south) onto Floridian Way, which merges onto World Drive (southbound).