Take the bus to dowtown disney and then take the bus from there back to the grand floridian. In the alternative, you can take a bus to any of the parks that are open and then switch from there. Having stayed at AKL this past trip, I can tell you that it took us awhile to get from there to downtown disney (partially b/c of bus waits.....partially b/c of the way the roads are laid out). If it were me, I'd hop on whichever bus came first to a location I knew was open (dowtown or a park) and then switch as appropriate (monorail, boat, bus).