JR Pass scheduling

I am visiting Japan May 8-18. I'm not sure for what length of time I should by my JR rail pass. I am leaving flying to Narita and traveling straight to Osaka.

Schedule:
Osaka May 8-10
Kyoto 10-12
Nagoya 12-13
Tokyo 13-18

Should I get a 1 week pass (which would fulfill my travel needs outside of Tokyo) or a 2 week pass (which would cover some trips in Tokyo and the ride back to Narita.) Or is there a better/cheaper way to get around Tokyo and back to Narita (bus/subway/taxi/etc)?

I was disappointed to find out the NEX/Suica package deal does not work on the return trip to Narita. Are there any offers like that going to the airport?

Thanks for your help!

A one week pass covering 8th-13th is what you need. The extra expense of a 14 day pass would be much more than buying individual tickets in Tokyo. The cheapest way back to the airport would be via the Keisei Line Limited Express, 70 minutes, 1000 Yen, from Keisei Ueno station.