In The Giver, what is the most important of the memories that the Giver gives Jonas?

I will identify two memories that I think are the most
important that the Giver imparts to Jonas.  They are the memory of the war and the
memory of the Christmas scene.

These two memories give
Jonas a really good idea as to both the good and the bad of what can happen in a society
that is less controlled than the one he lives in.  He sees the good of his society -- it
prevents the tremendous pain and suffering that happens in war.  But he also sees the
downside of his society.  He sees how happy people can become when they have families
and love as in the Christmas memory.

These two memories,
then, give him a pretty balanced view of what life in a different kind of society would
be like.