Need to know if I can use JRPass inside Tokyo

Hello

I am coming to Tokyo by next day, and I am planning to stay like 12 days (me, my wife and 3 kids), I am planning to stay in Tokyo, go to Fuji/Nagoya/Kyoto and ended in Osaka.
questions: can I use this pass inside Tokyo and Osaka, I mean between areas.
my hotel is close to Nishi-Kasai Station, is it worth to buy it to go around, like Disneyland, city center....same for Osaka, staying close to Shin Osaka Station and planning to go to Kyoto/Universal Studio.
Please let me know.