Best Glide, Minimum Sink, Emergency control settings.

AOPA Article on Best Glide

Best Glide as published in the POH is generally at max weight---it is lower when the plane is flying below max weight. 

Best Glide is speed that allow the greatest distance for a given sink.  Minimum Sink is another spec that provides the least sink for a given time.  In an emergency situation, more time is generally my biggest goal.

The AOPA article essentially describes the settings---engine at idle (it may already be stopped in an out of fuel or mechancal failure emergency)---gradually input maximum nose up trim--let the plane fly itself with no elevator input--keep the inclinometer ball centered. The plane will descend at a speed above stall speed and the sink rate will be minimized.

This is also a very good method to use if you have to decend thru a cloud---maintain coordinated flight (ball in center) and use aileron to keep the compass fixed---you will descend slowly without turning. If the compass is fixed, you are not turning.  If you are not turning and you are coordinated with the ball in the center, then you are stable with wings and rudder set only to adjust to cross wind.