Hi Karen!
Disney´s Bus Transportation is very reliable, convenient and of course free. Resorts with fewer bus stops usually work better, but sometimes get to share a bus with other resorts. Disney´s Pop Century Resort and Port Orleans Resort - French Quarters are said to have the fastest bus system.
From my experience most resorts have similar traveling times to the parks.
It is very important to note that Disney bus system does not travel from resort to resort. Only the Monorail and some boats travel between some Disney Resorts.
During regular or low season Disney´s bus system is at its best and even then a taxi or a rented car will make a big difference in commuting times. By car I average 15 to 20 minutes from my room to the park and only when visiting Magic Kingdom do I need to ride the Monorail or boat at the Transportation and Ticket Center - 15 to 20 more minutes. Parking at the parks and the Ticket and Transportation Center is free for guests staying at a Disney resort.
So far I have had a great experience when Disney´s bus transportation, but most rides take around 60 minutes, more or less. The commute includes walking to the bus station, waiting the bus and the ride which may include one or more additional stops.
I love staying at Disney´s Contemporary Resort or at the Polynesian Resort, but I also like the convenience of driving to the parks and the airport.
Thank you for visiting and letting us help you plan a magical Disney vacation.
Miguel