I can't pick just one song for "Best" - impossible.
Best:
Asleep in the Back - Scattered Black and Whites/Powder Blue/Asleep in the Back
Cast of Thousands - Switching Off/Fugitive Motel/Ribcage
Leaders of the Free World - Great Expectations/My Very Best/Station Approach
The Seldom Seen Kid - Friend of Ours/Weather to Fly/The Loneliness of a Tower Crane Driver
Build a Rocket Boys - The Birds/Dear Friends/Lippy Kids
Special mention to: Mirrorball and The Bones of You from Seldom Seen Kid..... basically, the whole album! Seriously can't fault it.....or at least, not much!
Worst:
Asleep in the Back - Bitten by the Tailfly - really don't like it. Not Elbow at all.
Cast of Thousands - Grace Under Pressure - it has grown on me a little but still don't see the appeal.
Leaders of the Free World - The Everthere (not sure why, but just find it a little.....flat....lyrics are amazing, though, as ever).
The Seldom Seen Kid - Grounds for Divorce (I actually like this song, so it should tell you a bit about how much I like the album..... not quite up there, though, for me.....and again, a bit too macho for Elbow IMO).
Build a Rocket Boys - High Ideals - it's okay. Just okay. Nice rhythm. but it doesn't really do it for me.