If you were wondering what time the shops and restaurants on the Boardwalk close, I recall it varies a bit. I think the ESPN CLub is open until about 1:00 am. JellyRolls is also open late (1 or 2 am?). I think the majority of other places close around 11 pm.
This is off the top of my head from our trip last September, which usually is a quieter time of year. Someone who has been more recently might have more accurate times, but this should give you an idea.
If you're visiting the BoardWalk and have a car, that will certainly be easier than bus transportation. Lately when we have been at the Boardwalk, the resort shares busses with Swan/Dolphin and Yacht/Beach, so the bus ride can be quite crowded and lengthy. In our experience, if you let the guard know you are visiting the BoardWalk area, you may be given a 3-hour pass and be permitted to self-park (make sure you have your All-Star parking pass visible in the window). This would be easier to obtain after EPCOT has closed, as BoardWalk does not provide theme park parking.
Hope that helps a bit!