We went to the 9:30 HDDR show in 2005 (best time to go to HDDR, IMHO, and we've been a lot). After the show all of the parks were closed so the bus area had two busses waiting that said something like "Walt Disney World" on their lighted sign. We just asked one of the bus drivers where they were going and they told us whether or not to get on their bus or the other. The bus drivers are usually very helpful. By the way there were only a handful of people even taking busses back to their resorts (there was only about 30-40 people even at the HDDR) and they wait for awhile for people to make sure no one else is coming.