What a great idea!
I would include music from when he was born (1927?) and music that represents each decade that the pictures were taken in. So, break up the pictures into sections - the 1920's, 1930's, 1940's, etc... Maybe for wedding pictures include their "song".
From the year he was born (and an extra one):
1927 - Star Dust by Hoagy Carmichael
1928 - Keep on the Sunny Side by The Carter Family
A-TISKET A-TASKET by Ella Fitzgerald
Somewhere Over the Rainbow by Judy Garland
Three Little Fishies by Kay Kyser
INDIAN SUMMER by Tommy Dorsey
WHEN YOU WISH UPON A STAR by Glenn Miller
G. I. Jive by Johnny Mercer (this is great if he was in the service)
MAIRZY DOATS by Merry Macs
Sentimental Journey by Doris Day (this would be great if you're only wanting one song)
I found these and a WHOLE bunch more, here: http://ntl.matrix.com.br/pfilho/html/top1/
Here are the top songs by decade (but they start with the 50's.)