The Westin is in a fine location and it's a very good hotel; the finest choice among the three *wood properties.

The Yokohama and Tokyo Disneyland properties are about 30 minutes from Tokyo station (in different directions) as railroadtycoon noted. However, Yokohama is the second biggest city in Japan with plenty of night life and shopping in its own right while the Disneyland area is pretty much isolated from anything interesting except the two Disney amusement parks.

I would chose the Yokohama location over the Tokyo Disneyland location any day. It's not that bad a place to be! Yokohama is also halfway to Kamakura if you want to do a day trip there.

At least half of the Narita Express trains make Yokohama station their second or third stop after leaving the airport.
Note that even if the Sheraton is within 200m of the station, it could be hard to find the first time on arrival. Study the map on the hotel's website!