The boat from POFQ to DTD docks at the Marketplace area. As you exit the boat, Captain Jack's Restaurant will be on the on right side, and the Rainforest Cafe, which is 5 or 6 steps up from the dock, will be on the left side.
Yes, there are buses. The bus stop for the Port Orleans resorts (both POR and POFQ) is Stop #1 at the Marketplace Section, and at Pleasure Island its the Stop closest to the shopping area (can't remember if this is Stop #1 or Stop #6). Signs at the bus stations will direct you to the correct Stop. Keep in mind that the PO/DTD buses also stop at Typhoon Lagoon somewhere along the route which may add to your travel time.