7 Day JR Pass suitable for me?

Hi Everyone, I will be visiting Japan in end Mar. My itinerary is as follow:

Day 1: Arrival at NRT
Day 3: Proceed to OSAKA via Shinkansen
Day 4-5: Will visit Kyoto/ Hiroshima by Shinkansen
Day 6: Return to Tokyo via Shinkansen
Day 9: Fly out of Tokyo
If getting the pass is suitable, I will activate it on Day 3 - Day 9. Thus, can I reserve a seat for train to Osaka on Day 1 arrival at Tokyo but get them to activate the 7 day pass from Day 3 onwards?? Appreciate yr advise. Thanks!!

Yes, a 7-day pass is suitable for you.

Can I reserve a seat for train to Osaka on Day 1 arrival at Tokyo but get them to activate the 7 day pass from Day 3 onwards?

Yes, that is possible.

Thanks Uji. By the way, is there any counter whereby I can do the reservation at JR Ueno Station or NRT? As for the activation of the JR Pass on Day 3, do I need to go to the JR counter to activate the pass before I can use it? Thanks!!

is there any counter whereby I can do the reservation at JR Ueno Station or NRT?

I assume you refer to the Narita Express. You can make reservations for any JR trains at the ticket counter of any JR station, including Ueno Station.

As for the activation of the JR Pass on Day 3, do I need to go to the JR counter to activate the pass before I can use it?

No. You set the start date at the time of exchange. No further activation is needed on the start date itself.

Thanks so much Uji.

By the way, I also would like to experience snow. Thus, I will be going to Gala Yuzawa as I believe its the most easily accessible. However, I tried to search on http://www.hyperdia.com/ on the Shinkansen but I can only find them going to Echigo-Yuzawa. Is there any direct Shinkansen to Gala Yuzawa from Tokyo in Early April?

Service to Gala Yuzawa stops on March 23.

Oh. So is Gala Yuzawa still open at around first week of April 08? If so, how do I get there since there's no more services to Gala Yuzawa? Thanks.

No, sorry, I made a mistake. Service to Gala Yuzawa is only reduced, but not stopped after March 23.

There will be a smaller number of trains operating to Gala Yuzawa Station until May 6.