score:1
Layover #1 - 13 hrs, need to switch airport from Narita to Haneda. Lands 8:30pm, departs at 10am.
It will take 60-90 minutes to get out of Narita, the express trains will have stopped running by then. Regular trains and buses run until about 11pm which gives you an hour to figure the buses out.
Layover #2 - 12 hrs, need to switch airport from Haneda to Narita. Lands at 11pm, departs at 11am.
It will take 60-90 minutes to get out of Haneda, the trains will have stopped running by then. But Haneda is a short taxi ride from central Tokyo so less of a problem.
I would recommend that you book a room at each airport - any arrival delays will mean you will be too late to get into Tokyo. Transportation starts very early in the morning, you won't have any problems getting to the other airport.
Central Tokyo to Haneda is about an hour, you will need to be there at least 90 minutes before departure.
Central Tokyo (or Haneda) to Narita is 2 hours. And you need to be at Narita at least 2 hours before your flight. So that means checking out of your hotel at 6am, latest.
Published times of 55 minutes to Narita are platform-to-platform times of a limited express train that runs twice an hour.
Upvote:2
How many days do you have? :) It really depends on your tastes
On this site from the NHK TV of Japan, you have a program which only discusses Tokyo, and I see it here in Portugal, so you can imagine it has plenty of info :) :)
You can try the Akihabara district for electronic stuff, the night life of the Shibuya district...
But if you want a guide, try this which will tell you where you need to go in every hour.
Hope this helps you :) Happy Tokyoing