Little Lies is my top choice for the #1 spot. It just oozes the '80s without being so cheesy about it.
Don't Stop and Hold Me were so damn close. It's funny how both of them were a Chris and Linds duet. They should have had more of those.
Personally, The Chain should have been a single. It would have definately been number 1. Then they all could have said they had a #1 single.