Help to check our itinerary and jrpass

Dear all,
My husband and i are going to japan for the first time. I would like to know if buying a JR pass is worth it for our trip. And when is the best day to activate it.
Here is our itinerary:
13 april - arrive in haneda airport at 1030 pm. We are going to stay st GRand park hotel panex tokyo near the airport. What transportation can u suggest to get there?
14- disneysea.
15-16 then go to hakone. Hotel in hakone.
16- 19 hotel stay in kyoto
17-explore kyoto
18- daytrip nara
19-daytrip osaka
20- . Check out kyoto hotel . Daytrip to hiroshima and go back osaka. Stay in osaka.
21- fly of from kansai airport.

With our itinerary is it worth to buy a jr pass?what are the tickets i need to take? Can you show me the detailed legs and how much i can save? Sorry i have lots of questions as its going to be our first time and its better to know from the best.

Let me know. Thanks in. Advance!

-patyr