This is especially true on I-4, which can turn into a parking lot at certain times of day. Visitors driving a car need to allow some additional time for 'sitting' and a good map is essential before any timesaving short cuts are attempted. Rental cars can be collected at Orlando and Sanford International Airports - at Orlando International a short bus ride is required for some of the rental companies. Taxis and shuttle buses also run from both airports to the main tourist areas, and you can use these to get around town during your stay if required. When headed to a theme park from your hotel ask for the fare when you call a cab as set rates often apply.
Many hotels offer a free shuttle to the bigger theme parks, which can be a big money saver.
Likewise guests staying in Disney accommodation have free use of the Disney buses, ferries, and monorails. The service runs every 15 minutes or so.