Not to confuse you, but there is an easier way to get to the Vistana. It is the "road less traveled" and will make all the difference.
Most visitors to Orlando exit the airport via the North exit, as jfulcer suggests, but the traffic along this route makes it a frustrating beginning to an otherwise magical trip. I, however, avois I-4 at all costs. The following route is not only a shorter route, but a less congested route, as well, thereby making is MUCH quicker and relaxing.
Exit the Airport through the South AIRPORT EXIT.
This road becomes S. ACCESS RD. and then becomes BOGGY CREEK RD.
Take the SR-417 South ramp, merge onto CENTRAL FLORIDA GREENEWAY (Portions toll).
Take the INTERNATIONAL DR exit (exit number 6) towards SR-535/I-4 E/SR-356.
Keep LEFT at the fork in the ramp.
Merge onto WORLD CENTER DR. (SR 536)
Turn RIGHT onto S. APOPKA VINELAND RD. (SR 535)
Turn LEFT onto VISTANA CENTRE DR.
Last trip, this route took less than 30 minutes. I-4 alone will take longer than that during most times of the day.
As for closeness to Disney, when exiting the resort, turn right (not left towards I-4) if you are going to any location other than Downtwn Disney. Once out of the resort, turn right at the first light onto SR 536. This road leads right onto the property and is quicker than the main access road if you are going to most of the parks.
Any other questions, I'll be glad to answer. You'll love the location of Vistana. It's close enough to limit driving, but not in the congestion of other tourist areas like 192.