Thanks for the replies so far. I'll make sure that the toll road is open, good to hear that all 5th stations should be accessible.I'm not going by rental car but rather use my own, and as I'll have the family in the car (including two daughters, 5 years and 1 year) climbing Fuji is not an option. We'll start by staying at the Yunessun Inn and spa - their weird tea/wine/coffee/sake baths seems to be too odd to miss. And as we're already in the area, why not drive closer to Fuji while we're there?
Again, thanks a lot so far and if you have more input/info please let me know.