we like the "back" way. Sherbeth road, off 192.
we exit the turnpike on 429. take it to 192. turn left and go to sherbeth road. it brings you to Osceola parkway. turn right and it takes you to buena vista drive . (no fanfare, though)
western way, also off 429 is a great way to get to buena vista drive.
from the east, off Apopka/vineland road, is the entrance to the disney hotels (by the Crossroads shopping center) this is also buena vista drive, which is pretty much tha main east/west raod through disney property.
ask your resort to send you a map of the disney property. it's good, cause it also shows which intersections are stoplights, and which are ramps.
but, since a lot of people mistakenly believe Magic Kingdom IS Disney, World drive is usually considered the main gate. (kissimee motels will define themselves by "main gate, east gate)