JR Kanto Pass

Hi There,

I would like to ask about JR Kanto Pass as i will be purchasing it in Narita airport on 20 Nov...Is the Kawaguchiko and Otsuki covered by his pass which is operate by Fujikyu Railways.
and also if i choose to take the Limited express between Otsuki and Shinjuku is also cover by Kanto Pass??

I also check hyperdia for the train timing but some showing within 2 to 3 mins to change train...Since there are various platform and i m travelling with children do u think i have time for that kind of transfer...
Pls advice...

Thank You