keisei express and metro pass

We are only in Tokyo for 2 days, staying in Asakusa. We expect to buy keisei express to and from airport. Is it better vlaue to get a 1 or 2 day metro pass, then but individual metro tickets the second day.we are only going to be travelling to major tourist sites like temples and the government tower sony plaza etc and back to narita

Presumably you mean
- Keisei Slyliner by "keisei express"
- Tokyo Metro Special 1-Day / 2-Day Open Ticket by "1 or 2 day metro pass"
- Tokyo Metropolitan Government Buildings by "government tower"
.... Is that right?

A Tokyo Metro Special Ticket is valid only for Tokyo Metro company lines (9 of 13 Tokyo subway lines). It does not cover any section of Toei subway lines (4 of the 13 lines).
There may be cases where a route via Toei subway is most convenient for visiting a tourist site.
- Tokyo Subway Route Map
http://www.tokyometro.jp/global/en/service/pdf/routemap...
(Asakusa is on the upper right of this map.)
- Convenient Value-added Tickets
http://www.tokyometro.jp/global/en/ticket/valueticket.h...

Sony Plaza was renamed as "PLAZA" and is now run by PLAZASTYLE Corporation.
Which shop of PLAZA are you hoping to visit? If you mean PLAZA shop of Ginza, that is in Ginza Sony Building, on Basement floors 1 and 2, open from 11：00 through 21：00.

Tokyo Metropolitan Government Buildings
http://www.metro.tokyo.jp/ENGLISH/TMG/map.htm
Station: Tochomae Sta. of Toei Oedo Line: A4 Exit.
Station: Shinjuku Sta. of JR: South Exit., turn right, about 10 min. walk.
- From Asakusa Sta. of subway: not via Toei subway
Ginza Line train, about 5 min. -- Ueno Sta. -- walk -- Ueno Sta. of JR -- Yamanote Line train for Ikebukuro, about 25 min. -- Shinjuku Sta.
- From Kuramae Sta. of Toei
Toei Oedo Line train for Hikarigaoka, about 20 min. -- Tochomae Sta.
- From Asakusabashi Sta. of JR / Toei
JR Sobu & Chuo Local train for Nakano, about 20 min. -- Shinjuku Sta.

Ginza Sony Building
http://www.sonybuilding.jp/e/access/index.html
Station: Ginza Sta. of Tokyo Metro: B9 Exit.
(This exit is far from Ginza Line platform. Marunouchi or Hibiya Line seems preferable.)
Station: Yurakucho Sta. of JR: Chuo Exit [Central Gate], turn left, about 5 min. walk.
- From Shinjuku Sta. of Tokyo Metro Marunouchi Line
Marunouchi Line Train for Ikebukuro, about 15 min. -- Ginza Sta.
- From Asakusa Sta. / Kuramae Sta. / Asakusabashi Sta. of Toei
Toei Asakusa Line train for Nishi-magome, about 5 min. -- Ningyocho Sta. -- Hibiya Line Train for Nakameguro, about 10 min. -- Ginza Sta.

//