Walk or boat to Studios and Epcot. Boats run Epcot - BWI/BWV - YC/BC - S/D - Studios - S/D - YC/BC - BWI/BWV - Epcot. Trip to and from Epcot that way is under 10 minutes, trip to and from Studios can easily be 30. However, the S/D dock is a short walk right over the bridge from the end of the boardwalk and thus you can choose to use that stop for BWV.
Walk to Epcot is about 10 minutes casual pace, to studios about 20 to 25 (if at rooms that are far from lobby, you can exit via stairs and have the shorter time walk).
For other parks and DD, you use bus (unless you have a rental car which you will wish you had after using the BW buses). There is one bus stop at BWI/BWV which is on the BWI side of the resort. It shares buses with Swan and Dolphin which are two stops and sometimes also with YC/BC which adds another two stops. BW is usually, but not always, the first stop hit before going to a park and the first hit when coming back. Buses can be crowded and sometimes standing room only for BW patrons during early morning rush time if they switch order of usual stops, which they sometimes do. Other times of day usually not an issue except when bus is running late (all too often), meaning much longer than the expected 20 minutes or so between buses. Be aware that at BW, lousy bus service seems to be the norm and not the exception (personal view it is the worst system on site). All too often you wait a long time for a bus going or coming (and a long time can sometimes mean 50 minutes or more).