One day Subway Ticket for railways?

Can I use Subway Ticket (one day pass) for railways?
Should I buy that ticket pass if I only go to Disneysea and Disneyland? Or its better to buy the tickets for each train directly?

From which station? which hotel(or)?

"Maihama" is not subway's(Toei/Tokyo Metro) station.
http://www.tokyodisneyresort.jp/en/access/index.html

The subway pass will only work for subways. Maihama (closest station for Disney) is not a subway station. Just use an IC card - a lot of the one-day passes are hard to make pay off, especially if you're just spending the day at Disney and not going anywhere else.

I will spend all day long in Disneyland and the next day in Disneysea. I stay at a hotel around Asakusa, I wonder is that Ticket for subway is useful enough for a day? What do you guys suggest, buy the one day pass subway ticket or other?
I had checked in Hyperdia how to get there and most of all using trains but I can't ensure some trains are included in Subway or not. How do I know?

If the train icon color is purple/pink, then it's not JR. If you're trying to use it to go to Disneyland, then it's not valid, so I wouldn't get it. Use an IC card, which is valid on all rail transport in Tokyo, JR, Tokyo Metro and other rail lines.