That would be Ballad Of Spring Hill (Spring Hill Disaster). Happened in Spring Hill, Nova Scotia. It was written by Peggy Seeger, but also performed by Peter, Paul & Mary.
LifeOnWry, you just put me in mind of Mining for Gold, another one that can do it for me. It has family associations for me.
Can’t you feel the rock dust in your lungs?
It’ll cut down a miner when he is still young.
Two years in the silicosis takes hold.
And I feel like I’m dying from mining for gold.
I feel like I’m dying from mining for gold.
TB Sheets, by Van Morrison, can affect me for much the same reason. The part where he’s making excuses to leave his dying lover’s room… just tears me up. After tending to dying family, knowing what that’s like, and the crushing, overwhelming, unrelieved regret that comes to you unbidden, thinking, “I could have done more… I should have done more… it would have been such a little thing to do… why didn’t I do more?”
I think you’re refering to “Ice Cream” by Sarah Mclachlan (Your love is better than chocolate is one of the lines in the song, however).
It has the same effect on me, for pretty much the same reason.
Louis Armstrong’s What a Wonderful World gets me, probably because of the kind of movies I usually see it featured in.
Warren Zevon’s Please Stay is probably the worst for me, though. It’s in the same category with Tears in Heaven as songs I wouldn’t even think twice about if I didn’t know the story behind why they were written. It reminds me a lot of some of the feelings I was having when I was waiting to hear my prognosis, and also of how different his was from mine.
Seasons in the Son and the mentioned Cats in the Cradle.
Well that was almost spelled right… I’ll add some lyrics while I’m at it:
Seasons in the Sun by Terry Jacks:
Goodbye to you, my trusted friend.
We’ve known each other since we’re nine or ten.
Together we climbed hills or trees.
Learned of love and ABC’s,
skinned our hearts and skinned our knees.
Goodbye my friend, it’s hard to die,
when all the birds are singing in the sky,
Now that the spring is in the air.
Pretty girls are everywhere.
When you see them I’ll be there.
We had joy, we had fun, we had seasons in the sun.
But the hills that we climbed
were just seasons out of time.
I think you’d be right on this one. 
I heard it in the movie then used a keyword search and downloaded it. That’s just what the file was called, I never really though hard about the title.