If I had to pick one (which is impossible) I will go with the more upbeat one called 'Trees':
O is also for OF MONSTERS AND MEN: They are slightly more well known band from Iceland. Their first EP album called 'Into the Woods' that came out in 2011, and then released their first full album called 'My Head is an Animal' early this year I think. They released a single called 'Little Talks' that went to number one in Iceland.
Love and Peace.