I recommend staying in Ginza or Shidome. Ginza is very close to the Tsukiji fish markett. If you are interested in seeing the morning tuna auctions. Mind you they start at like 5:30AM. Ginza is the most high end distrct in Tokyo with many flag ship international shops.

The restaurants are great and it is only about 20 mins from HND and exactly 1 hour from NRT term 2. The Narita express boards from Tokyo station every 30 mins, but I suggest you get the schedue from the ffront desk ar your hotel. It changes frequently becuase of the electricity problems after the tsunami.

Shinjuku Is great for night life and so is Shibuya but they are a little further from NRT. 90 mins by Narita express.

Enjoy^