I think "Forever Young" by Rod Stewart makes a good slide show song. I played it in the senior slide show at my high school yearbook party right before graduation and even the guys were in tears.
"These are Days" by 10,000 Maniacs is always a good one.
"You Ain't Never Had a Friend Like Me" from Aladdin!
"You've Got a Friend" James Taylor
"Lean on Me" or "Stand By Me"
"Feels like home" by Chantal Kreviazuk is good as someone mentioned above.
Another good song that is also from Dawson's Creek and has lyrics similar to "feels like home" is "Never Saw Blue Like That" by Shawn Colvin. I think Kappa uses it a lot because of the blue references.
Never Saw Blue Like That
Performed by Shawn Colvin
Written by Tom Kimmel, Jeff Franzel, Mark Luna
Today I took a walk up the street
And picked a flower and climbed the hill
Above the lake
And secret thoughts were said aloud
We watched the faces in the clouds
Until the clouds had blown away
And were we ever somewhere else
You know, it's hard to say
And I never saw blue like that before
Across the sky
Around the world
You've given me all you have and more
And no one else has ever shown me how
To see the world the way I see it now
Oh, I, I never saw blue like that
I can't believe a month ago
I was alone, I didn't know you
I hadn't seen or heard you're name
And even now, I'm so amazed
It's like a dream, It's like a rainbow, it's like the rain
And somethings are the way they are
And words just can't explain
Cause I never saw blue like that before
Across the sky
Around the world
You've given me all you have and more
And no one else has ever shown me how
To see the world the way I see it now
Oh, I, I never saw blue like that before
And it feels like now,
And it feels always,
And it feels like coming home
I never saw blue like that before
Across the sky
Around the world
You've given me all you have and more
And no one else has ever shown me how
To see the world the way I see it now
Oh, I, I never saw blue like that before