These hotels are listed on pp. 104-5 of the 2004 PassPorter. The PassPorter Guide gives great descriptions of each hotel. They are located on Hotel Plaza Boulevard. This collection of hotels have been referred by several names over the years.
The Disney Hilton is the only hotel among this group that is able to offer the Extra Magic Hour and E ride night perks.
The Wyndham Palace Resort and Spa and the Grosvenor Resort along with the Disney Hilton are the three hotels that are closest to Downtown Disney and are only a couple of minutes of a walk. Further down the street on Hotel Plaza Boulevard is the Holiday Inn (formerly Courtyard by Marriott), Doubletree Guest Suites Resort, Hotel Royal Plaza, and the Lake Buena Vista Best Western Resort.
A word about transportation - If you plan on staying at any of these hotels, I highly recommend getting a rental car. While they advertise shuttle buses to the Disney parks, the timing is not very often, inconvenient, and they drop you off quite far from the park entrances. Yes, you could just walk over to Downtown Disney and pick up a Disney transportation bus. However, they frequently don't leave Downtown Disney early enough to get you to a park in time for park opening. This is key as far as I'm concerned when it comes to touring the parks at WDW. All hotels in this area with the exception of Hotel Royal Plaza and Best Western have a rental car desk.
You can check out the hotels by surfing to:
http://www.doubletreeguestsuites.com http://www.grosvenorresort.com http://www.hotel-inside-the-park.com http://www.royalplaza.com http://www.orlandoresorthotel.com http://www.wyndham.com/hotels/MCOPV/main.wnt
I have not personally stayed at any of these. I have heard several dismaying reports regarding the Grosvenor. The one key thing to keep in mind about the Hotel Royal Plaza is that the tower rooms are MUCH better than the pool side courtyard rooms.
Hopefully others can add some insight.