Disneyland will be very packed.
Get ready for very very long Q
My record was 2 hour of Q just at main entrace Gate.

How many person?
Chances of getting 1 seat was 20%
Chances of getting 2 seat was 10%
More than 2 seat was 5%

That why I post very big at Page 1
Avoid Golden Week and Bon Odori at ALL COST

During Golden Week. All JR Train will be Priority 1 week earlier reserved for Japanese. 
This means most of Japanese will be reserved the train seat already earlier than you.
You still can travel to Nagoya in Unreserved Seat coach.  99% U will standing at Aisle from Tokyo all the way to Nagoya for sure.
Very tiring.

What is your plan at Nagoya?

Based on my 504th Trip to Japan Experience. Tok Guru Exp.
My Suggestion on you was Forget about JR Rail Pass, Forget about Nagoya
Stay at Tokyo only. Avoid any City to City Transportation.

During Golden Week. Reservation seat only reserve for Japanese. 1 week earlier than any foreigners from oversea.
Your chances are only unreserved seat coach. Get ready standing from Tokyo > Osaka > Tokyo
The best of Using JR Rail Pass on Unreserved Seat Coach was you can keep on trying to boarding into the train.
Example:

08:00 Hikari Class
Too many people in Unreserved seat.
Then you can try bounce into the next
08:20 Hikari Class
too Many People again
Then 8:40
the list keep on going.
Find a coach which you think lesser people which is nearly impossible on Golden Week.......

Just pray to god got people in front of you getting down at Shizuoka Station and Nagoya Station. So you got chances to takeover the seat.
to the worst 2 and half hour standing all the way to Osaka Station. 

Time to do some exercise. 
My Best Advise for you still...forget about City Hopping. Just Focus at Tokyo Only.
Your Visiting Japan timing are totally most worst. The Middle of Golden week.  Most Chaos Most Expensive time.....

During Golden Week. Reservation seat only reserve for Japanese. 1 week earlier than any foreigners from oversea.
Your chances are only unreserved seat coach. Get ready standing from Tokyo > Osaka > Tokyo
The best of Using JR Rail Pass on Unreserved Seat Coach was you can keep on trying to boarding into the train.
Example:

08:00 Hikari Class
Too many people in Unreserved seat.
Then you can try bounce into the next
08:20 Hikari Class
too Many People again
Then 8:40
the list keep on going.
Find a coach which you think lesser people which is nearly impossible on Golden Week.......

Just pray to god got people in front of you getting down at Shizuoka Station and Nagoya Station. So you got chances to takeover the seat.
to the worst 2 and half hour standing all the way to Osaka Station. 

Time to do some exercise. 
My Best Advise for you still...forget about City Hopping. Just Focus at Tokyo Only.
Your Visiting Japan timing are totally most worst. The Middle of Golden week.  Most Chaos Most Expensive time.....

ic, thanks for the info.

u can buy this pass at the airport and other selected places in Tokyo :

[Airports]
Haneda Airport (International Terminal Visitor Information Center)*1, Narita Airport*1 and Yonago Airport*2

*1: Only sold to overseas visitors on tourist visas. (Passports will be checked)
*2: Only sold to airline passengers.

[Other Places of Purchase in Tokyo]
1. BIC CAMERA and Sofmap
BIC CAMERA Yurakucho Store, BICQLO BIC CAMERA Shinjuku East Store, BIC CAMERA Akasaka-mitsuke Station Store, BIC CAMERA Ikebukuro Main Store, BIC CAMERA Shibuya East Store, BIC CAMERA Shibuya Hachiko Store, BIC CAMERA Shinjuku East Store, BIC CAMERA Shinjuku West Store and Sofmap Akihabara Main Store
*Passports will be checked.

2. Laox
Laox Akihabara Main Store, Laox AsoBitCity Store, Laox Shinjuku Main Store, Laox WATCH, Laox Ginza Main Store and Laox EXITMELSA Store

*Passports will be checked.
3. HIS Tourist Information Center
Shinjuku Head Office, Shinjuku 3-chome, Ginza Head Office, Ginza Core and Harajuku
*Passports will be checked.