Welcome from Calgary!
Nine days will be great. Our longest was 14 days and we just took our time. For that trip we had a 10-day pass w/ Water Parks. We kept a couple of spare days for relaxing at the resort, running a couple loads of laundry, etc. For the remaining 12 days we visited each park at least twice and had 3 water park days.
We only leave WDW for the odd external adventure (say Universal Orlando, Cape Canaveral, etc). Otherwise there is no real reason to leave and you can get from A to B using the on-site bus network.
I tried driving on-site once years ago - the traffic itself isn't bad, I just kept getting turned around!