My Favorite FFXI song is The Sanctuary of Zi'Tah (I frequently take "vacations" to the Sanctuary just to listen to it.)
http://www.youtube.com/watch?v=gHGUmnrkYi8

My favorite song from FFXIII is Blinded by Light (consequently it's my favorite song ever)
http://www.youtube.com/watch?v=xfu0XBf8kmk

My Favorite song from FFV is Battle on the Big Bridge
http://www.youtube.com/watch?v=sgZsvJZ_ivg

My favorite song from FFIX is Eternal Harvest
http://www.youtube.com/watch?v=mq6C10bgZKw

My favorite World Map song is... FFVI: Terra's Theme
http://www.youtube.com/watch?v=sT9ReWDV0IU