Help Please

My friends and I will be travelling to Japan the first time on January 17 2015.

I have a few questions:

1. We arrive in Kansai and go straight to Hotel Universal Port in the Universal Studios area, we go to Universal Studios and tour around Osaka for about 3 days. Question is: Can we use the JR Pass in going around Osaka, without buying additional train tickets?

2. From Hotel Universal Port, we then go to Mt. Fuji. Questions are: How long would be the travel time? What is the earliest time of train departure can we take? Is it advisable to do this in this season? Do we need to buy any additional train or bus tickets apart from the JR Pass? We are not planning to climb Mt. Fuji, we just want to get a really good view of it.

3. If Mt.Fuji will not work, we are planning to go straight to Shinjuku, Tokyo then go to Disneyland. How long would be the travel time? What is the earliest time of train departure can we take?Do we need to buy any additional train or bus tickets apart from the JR Pass

4. From Shinjuku Tokyo, we need to go back to Osaka Kansai Intl Airport. Questions are: How long would be the travel time? What is the earliest time of train departure can we take?Do we need to buy any additional train or bus tickets apart from the JR Pass?

5. In going around Tokyo, do we need to buy any additional train or bus tickets?

Thank you in advance for taking the time! I really need help in understanding how to go around Japan.