This is a link to the Vancouver Transit planning site You would be going from around the Yaletown Roundhouse to YVR if you leave your boat in False Creek. Check it out on Google Earth and you will have a pretty good idea of the layout and where the different transit stops are. You will go on the SkyTrain.
Last year when I tied up at the Fisherman's wharf behind the Burrard street bridge, I walked to the Olympic Village sky train terminal and caught the Canada Line skytrain which took me right to the airport. About $1.75 if I remember right. Old fart discount. If you anchor farther up False Creek you will be even closer to the terminal.