"Juniors Farm", or maybe "Jet", or maybe "Mrs. Vanderbuilt", or maybe "Eat at Home", or maybe "This One", or maybe "Souvenir", or maybe "Letting Go". That's a tough one, I'm sure there's more.
Maybe I'm Amazed The Back Seat Of My Car Beware My Love Wanderlust No More Lonely Nights Once Upon A Long Ago My Brave Face Somedays Beautiful Night From A Lover To A Friend
are the ten that impress me the most on a musical/lyrical level. As for "song of the moment", well, that depends on the moment, doesn't it!
I would find it really difficult to list my top 100 favourite McCartney songs, let alone just one, but if I was pushed to name just one of my favourite McCartney numbers, I would probably say Jet, which is why I chose it for my username.