Your hotel will provide a shuttle bus to the following locations:
TTC (For the MK)
Epcot
Disney-MGM Studios
Disney's Animal Kingdom
(All of the above are Lane 26)
Downtown Disney (Stops next to the McDonalds)
Typhoon Lagoon
Blizzard Beach
These busses are provided by Fleetwood Limousine (dba Bethany Travels). Although they do say DOWNTOWN DISNEY RESORT AREA on them, they are not Disney operated busses.
Disney Transport does not have any busses from the Marketplace or Pleasure Island to any theme park, or the TTC. The reason being is that they don't want folks parking at DTD for free, and jamming the lots. (Also, they want Hotel Plaza guests to use thier own transportation that is provided)