By Disney transport, to get to WL from POR you take a bus to the Magic Kingdom and then a boat from there to WL. Will likely take close to an hour for the entire trip including wait times. Best way is simply to get a cab at the resort (or have a rental car) which is about a 10 minute trip. As a rule, Disney transport is pretty good in getting you to the parks because those are direct trips. Going to another resort requires switching transports at a central location such as a park or Downtown Disney and those trips can often take well over an hour whe they can be driven by car or taxi in 5 to 10 minutes.
Busses to theme parks, including AK, usually start running an hour or more before park opening.