3 Days in Tokyo

I am to Tokyo through Narita.
I will arrive on Friday afternoon and will stay in a hotel around Tokyo Station.

I will only have Saturday and Sunday full day to do sight seeing.

Can anyone suggest me good places to go for 2 full days in Tokyo?
Also, what kind of Train Pass do I need to get for only 2-3 days in Tokyo?

Should I just use all prepaid?

Thank you,

If you keep a schedule, you can see most of the major sights in 2 days. Check the Tokyo guides and see what interests you, then plan your day based on which stations you'll be around (for example, day 1 could be Shinjuku/Shibuya/Harajuku etc. and Day 2 could be Ueno/Asakusa/Akihabara or something like that)

I'd just get prepaid.

There are many spots in Tokyo.
You can make enough Tokyo itinerary during 2 days.

Tsukiji, Tokyo Sky Tree, Ginza, Omotesando, Marunouchi etc..

I inform some English information site.
http://omotesando.or.jp/en
http://www.tsukiji.or.jp/english/index.html
http://www.tokyo-skytree.jp/en/
http://www.ginza.jp/?lang=en
http://visitjapaninfo.weebly.com/
http://www.marunouchi.com/e/shop?type=top

thank you for the answers and suggestions, i cant wait to be in Japan!!

FYI, I believe Tsukiji is closed on Sundays, please verify on the website. Tokyo Skytree can get pretty crowded at times so make sure your schedule can fit in a long wait to get to the top of the tower and that it is worth it for the entrance fee. LOL, when I went with my friend, I took a look at the lines and the fees and just took a picture from the base of the tower and went elsewhere! Other viewing areas are Tokyo Tower, Sunshine 60 building in Ikebukuro and the Tokyo Metropolitan Government Towers in Shinjuku. Only the Shinjuku site is free to enter.
As far as my recommendations, I wonder what your interests are. If you are into Japan anime, Akihabara is a must see. And I like the Odaiba area for things to see and do. There is also a fee based viewing tower at the Fuji building in Odaiba. Odaiba could easily take up half a day for you so I do not know if you can spare that much time. And for general Japanese culture, a visit to Asakusa is recommended.

if you haven't seen this yet: http://www.japan-guide.com/e/e3051.html