Still Confused, Suica or Pasmo

I'll be coming from Takayama by bus to Shinjuku where I'll be staying for 8 days. Plan to visit Nikko as well. Should I get the Suica or Pasmo?
Also which is the best mode to get to Narita airport T1?
I am better at taking instructions than crack my head. Thank you.

Access to Nikko is explained below. The recommended way depends on the location of your hotel and your budget:
http://www.japan-guide.com/e/e3805.html

Access to the airport is explained here. Again, the recommended way depends on the location of your hotel and your budget:
http://www.japan-guide.com/e/e2027.html

Suica and Pasmo prepaid cards are the best type of ticket to get around Greater Tokyo if you are staying in Tokyo for a few days or longer stay. It can also be used on some of the trains that go to the airport and Nikko.

To be specific, it can be used on all trains to the airport (except for the express supplement required for the Narita Express and Skyliner) and for all trains to Nikko (except shinkansen and express supplement on limited express trains).

To elaborate on what Uji has said.

Suica and Pasmo for the Tokyo area are essentially the EXACT SAME thing, they just have different names, but they do exactly the same thing in the Tokyo area.
The Suica card works on Pasmo systems and the Pasmo card works on the Suica system, essentially it doesn't matter which one you have in the Tokyo region.

Thank you so much for all your patience in replying. Looks like I will only get the hang of it when I am physically there.