I have researched this subject greatly b/c DH and I were 'supposed' to go this past April but it just came too fast and we couldn't pull together all the $ fast enough. Anyway, from everything I've read it is just as convenient to stay at a hotel in certain areas of Tokyo then in a Tokyo Disney resort. There is a train called the JR Keiyo Line that drops you off across from the parks, the stop for Disneyland is called Maihama. This train supposedly only takes 20 minutes (on the express) from the Tokyo station. Easy Peasy.
We were going to stay at the InterContinental ANA TOKYO hotel (
InterContinental ANA TOKYO | ANA TOKYO ) which is near downtown so we'd be close to all the lines easily accesible to Tokyo Disneyland and all the other sites we'd want to visit in Tokyo (It's only 11 miles from DL and only a few miles from the Imperial Palace). Staying at the Intercontinental we also know we'd be assured the comforts we're used to in a modern western hotel.
If you wanted to stay at a hotel still on the Tokyo side of the city but really close to DL there are some "official" Tokyo Disneyland hotels located on the eastern shore of Tokyo bay that actually have shuttle buses to the parks. Yet, you are still in Tokyo so seeing all the other sites is still easy. From what I've researched I'd suggest these "official" hotels with shuttle service to Disney:
Tokyo Bay Hilton:
Hilton Tokyo hotel
Sheraton Grande Tokyo Bay:
Sheraton Urayasu Hotels: Sheraton Grande Tokyo Bay Hotel - Hotel Rooms at sheraton.com
or Hotel Okura:
Hotel Okura
Of course there are the two resorts IN Tokyo Disneyland called the Ambassador and Hotel MiraCosta. I just couldn't justify staying in one of these since neither DH nor I have ever been to Tokyo and we wanted to see MANY more sights that just Disneyland. Although, these are gorgeous resorts and if I had to choose one it would definately be MiraCosta. The Ambassador is the more traditional one with it's version of Chef Mickey's and the very 'old Hollywood' looking "hyperion Lounge." MiraCosta is more of an old world European style resort with a very cool marble Venetian style pool, and some really unique looking restaurants featurning Cantonese, Mediterranean, and Italian dishes.
I hope you find everything you need and I CANNOT wait to hear about this trip. I am MAD jealous! I've wanted to go see Tokyo DisneySea since it's inception.