my top choices are A Man's a Man for a' That and the very poplular "Ae Fond Kiss"
I also like Westlin' winds and Such a Parcel of Rogues in a Nation.

Green Grow the Rashes-o always puts me in mind of a Scottish Conservation Projects working holiday. We were scything rushes to thatch an old cottage with. It was hard work and one participant kept saying he couldn't understand how Burns could wax lyrical about it. But we were having no dalliances on the side. I like the sound of the song anyway.

I often sing Ewan MacColl songs on or around Burns night; Ewan's birthday was 25 Jan 1915.