Yes, you are better off using one of the parks at a pick-up/drop-off spot. If you will be using any of the monorail resorts, take the MK bus. You can walk to the Contemporary from the MK or take the monorail. If you are going to WL, get to the Contemp. and take the boat from there or the boat from MK. The other resorts are a little iffier tho. If you plan on going to Boardwalk or YC/BC I would be tempted to get a cab. Otherwise you'll end up walking thru Epcot and using a day on your pass. You could take a bus to MGM and then take a friendship boat to these resorts. Or you can use Downtown Disney as a transfer spot.