Hi Rita,
We visited WDW with 11 people (one of whom was in a wheelchair and two children were in strollers), so we had quite a "load" with each bus ride. The bus system made it so easy! We never had to worry about booster/car seats, who was going to drive, and how to get from one place to another. Our party was always able to stay together; and if we felt we might be split up because of crowds, we would just let others on the bus and wait for the next one to arrive. I'm hopeful you will find the Disney transportation just as convenient and mindless.
The travel times from Pop Century to the various parks are as follows:
Magic Kingdom: 25 minutes
Epcot: 20 minutes
Disney's Hollywood Studios: 15 minutes
Disney's Animal Kingdom: 15 minutes
Downtown Disney: 20 minutes
The wait time for buses can be anywhere from no wait to 15 minutes on an average day.