YAY! SKILLS!!!
Assess the immediate danger, either from the plane, the environment, or other people in your party. Quickly spitball an initial action plan, such as moving people away from the crash site to a temporary rallying location. Bonus points if it provides some measure of natural shelter.
Although it is easy to blast the "Type A a**holes," there is a reason that law enforcement agencies teach their officers "command presence." This means portraying confidence and persisting, not necessarily sreaming orders at scared people. "Relax Francis. We have scared and injurred people here. We're NOT going to do a forced march up to the top of the mountain to wave at passing planes." We have a lot we need to do and not a lot of time. I'm counting on you to help these people through this."
Everybody needs a job. Start assigning people tasks. Assess who has medical or other useful training.
"Please help carry that injurred lady over to those trees. This guy will help you."
"You - I need you to walk Steve over to those trees and make sure he doesn't try to light a cigarette."
"Ladies - Pleas gather those children together and move them over that way. Let them know we'll be okay."
After the immediate situation has been addressed, (We are no longer in immediate danger of some yahoo igniting the plane and we have some idea of how many passengers are injurred and how severe those injuries are.) We can start looking to other issues. Fire and shelter will be priorities, given the weather conditions of this scenario. the plane may not offer much in the way of shelter, at least initially, if there is significant risk of explosion. Fuel might be helpful in lighting a fire, however.
Again, you have multiple survivors that will come from all walks of life. Some may be crew members who will either feel obligated to "lead" or at least feel some obligation to "hold it together" for the sake of the passengers. They may also possess useful information regarding equipment and material that may be available on the plane. They may also have some idea of what the airline and FAA actions will likely be and what the timeline looks like.
With the current wars in Iraq and Afganistan, a large number of active duty military personnel are traveling on commercial flights. there is a good possibility that you will have one or more among your survivors. These people have useful training, know how to handle stressful situations, are used to taking orders, and working as part of a team to accomplish a goal. They may be among your most helpful assets.
Rather than having everybody clustered together or working on the same task, it is much more efficient to have various teams working simultaneously. Teams can be assigned fire, shelter, water, scavenging the wreck, caring for the injurred, dealing with bodies, gathering firewood, etc. Make sure to set parameters. People should know when to be back by, and for those teams tasked with venturing out, they should have a clear idea of how far to go as well.
That's enough for now. I'll pick this up again in a bit.
-- FLIX
Sorry I couldnt resist
(same thing right?) 
), but not enough of these types of things, that will really come into use in a real situation......