My favorites:
A Song For You
Superstar
Top of the World
Hurting Each Other
Goodbye to Love
For All We Know
I went to my elementary school's Christmas concert the year after I had graduated there. I had always loved my elementary school music/choir teacher. That year, she had the kids in the choir sing "Sing." And one of the highlights was that The Carpenters, (Karen really,) came out and sang it with them.

I think Richard was off to the side paying piano as usual.
That must have been a great experience!!!
I just love Superstar. You can hear heartache in her voice. What a beautiful voice.