by the way, you can request a specific building, even a specific room number...
there is no guarantee that you will get it, but you can put in a request on your reservation (if you booked directly with disney)...
i've only done that when i've stayed in the RPC concierge (when i give them the numbers of the rooms that i know have a castle view - and they always come through)....i've never made a special request when i stay in one of the standard buildings, but you can...and they'll make an effort to accomodate you....(i've done this often in other WDW resorts and they always meet the request pretty)...
the "unoffical Guide to WDW" has descriptions of the various room locations and what to request....there may be places online with the same information, but i'm not familiar with them.....so i'd recommend the unofficial guide and putting in a request for a specific building if it's important to you...
ok....i just went and looked up the GF in the 2007 edition of the Unofficial Guide...
this is what he says (i've skipped sections that refer to lagoon views and have only included the garden view parts):
"of the five lodges, three (Conch Key, Boca Chica and Big PIne Key) have one long side facing the lagoon and the other side facing the inner courtyards and swimming pools......................
Less expensive rooms in the same building (Conch Key) that offer good views are 72-,73-, 74-, 11, 13, 15, 17, 19, 21, and 72-, 73-, 74-12 and 14 (Grand Floridian room numbers are coded. Take room 7213: 7 is the building number, 2 is the floor, and 13 is the room number).
Note that many Garden View rooms in Big Pine Key and a few in Boca Chica, have views obstructed by a poolside building. There are the worst views from any Grand Floridian room."
The two remaining buildings, Sugar Loaf Key and Saga Cay, face each other across the marina. The opposide side of Sugar Loaf Key faces a courtyard, while the other side of Sago Cay faces a finger of the lagoon and forested area. All these views are pleasant but not in the same league as those from the rooms listed above."
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So based on the above excerpt from the Unofficial Guide, it would seem that you should request a room in Conch Key. That will be your safest bet. However, as i said, the only time i made a request was when i stayed in the main building. When we stayed standard i just waited to see what they gave us (we got Boca Chica both times).