Actually, the Old Timey Singalongs do very well at the Seniors Home. Not everyone was hip to Gershwin in that era.
For the 70-75 crowd (my group) it would probably hit closer to their heyday if you focus on the 50’s instead of the 40’s. The early years of RnR, early doo-wop, late big band, and maybe even the early 60’s and pre-Beatle times.
As I see it, the 40’s were more for my parents’ generation. They’ve been dead since the 90’s. The gap generation between my parents and me (80’s-90’s) might prefer WWII-era tunes, but it would be safer and more generally appealing to come forward in time to the Eisenhower years for a place to get your playlist.
And for me personally I would listen to covers of things up to and including Funk, Disco, Bossa Nova, and other late 60’s and early 70’s stuff. My tastes didn’t stagnate in high school. And I don’t think a lot of folks my age would object to more recent stuff, either. I might suggest slowing down with Rap, though.
One more thing: Country from that period plays well with most audiences. Ray Price, Eddy Arnold, Johnny Cash, Sonny James, Marty Robbins, Patsy Cline, Loretta Lynn.
My dad (86 years old, born 1926) is in a nursing home, so I know the crowd. The staff is grateful for entertainment for the residents, who are old and usually physically and mentally impaired. To get them to sing along, the songs have to be easy to sing, with words everybody knows; this is more important than the age of the songs.
My mom (90, born 1922) came of age in the 1940s and relates best to music of that era. She’s been complaining about the new-fangled music since the 1950s: Dinah Shore could sing, Mariah Carey is just caterwauling.
Something I’ve discovered: the older people get, the more eclectic their musical tastes become. I’m now 57, and find that I like most styles and genres of music, all the way from classical to big band to the '60s and beyond. I even have a soft spot for those corny sing-a-longs from the turn of the last century because I grew up hearing them in Harveytoons on TV.
The more you’re exposed to different styles and genres, the more you come to appreciate them, especially when they remind you of a certain time and place. When Saturday Night Fever came out, I hated the soundtrack. Now I look back on it with pure nostalgia.
I think it’d be great for you to do a musical tour of the 20th century. By the time you get to the Disco Era, those old folks will be out of their chairs cuttin’ a rug!
Look at barbershop favorites, and also Mel Tormé/Rat Pack-type stuff.
Bye Bye Blackbird is always a hit. Second La Vie en Rose. Summertime and Swanee River. Stormy Weather is one of Holiday’s that everybody knows. Try some of Nat King Cole’s songs for livelier tunes, and perhaps some Ray Charles.
Bye Bye Blackbird was my first thought. And Mockingbird Hill.
One thing to remember about people my age (mid 60’s) is that while we grew up with Elvis and the Beatles, we also have fond memories of music our parents and grandparents enjoyed. My grandma loved Guy Mitchell and Frankie Laine and Johnny Ray.
I made my grandfather a CD of his favorite music a few years ago when he was in his late 90s (he was born in 1910). He requested Duke Ellington, Ben Bernie & His Orchestra, Paul Whiteman & His Ambassador Orchestra, Hoagy Carmichael, and Vincent Lopez & His Orchestra, among others.
My grandfather was from New York City and I don’t know if this was peculiar to him or if this was the way things were regarding music back then, but he only liked band leaders that were from the East Coast. I had suggested putting Ted Fio Rito & His Orchestra on the CD, but my grandfather turned up his nose at him for being a West Coast band leader.
Did someone say “sing-along”? Don’t Dilly-Dally On The Way!
I also cast a vote for The Log-Driver’s Waltz.
Bobby Darin’s songs are catchy and memorable, even if not written by him. Mack The Knife and La Mer (Beyond the Sea) come readily to mind.
A couple more – Side by Side and Sparrow in the Treetop. I sang these songs with my friends in the 50’s, but I think the songs are from the 30’s and 40’s. Midwestern oldsters will know these – not sure about Coastal oldsters (might be too sophisticated).
Thanks, everyone, for your suggestions 
I think everyone in Canada knows the Log-Driver’s Waltz. Hehe. I actually have its composer’s autograph.
When you say you play music, do you mean you perform it yourself or you play recorded music?
I perform music. I mostly play tunes unaccompanied on the clarinet (I try to find music that’ll work for just clarinet.) I sometimes play with a pianist (accompanied by a pianist), and sometimes I play ukulele and sing (though I’m not that great at the ukulele.)
OK. I think this means that things like big band swing wouldn’t work for you. It would probably be better to stick to songs.
One approach you could take is to play popular hits from the time your target audience was young. Most people form their tastes in popular music when they are between fourteen and twenty-five years old. Someone who is eighty today would have been fourteen in 1946 and twenty-five in 1957. Here are some songs from those years:
1946
Beware (Brother, Beware) (Louis Jordan)
Let the Good Times Roll (also Jordan)
Don’t Let the Sun Catch You Cryin’ (also Jordan)
Ain’t Nobody Here but Us Chickens (also Jordan)
Choo Choo Ch’Boogie (also Jordan)
Oh, but I Do (Nat “King” Cole)
I’m in the Mood for Love
(Get Your Kicks on) Route 66
You Call It Madness (but I Call It Love)
The Frim Fram Sauce
I Don’t Know Why (I Just Do)
On the Atchison, Topeka and the Santa Fe
One for My Baby (and One More for the Road)
Do You Know What It Means to Miss New Orleans?
1947
Almost Like Being in Love
Beyond the Sea
Heartaches
Move It on Over (Hank Williams)
Smoke! Smoke! Smoke! (That Cigarette)
1948
Baby Face (this song had a revival that year)
Cool Water
A Couple of Swells
I’m Looking Over a Four Leaf Clover (also revived that year)
Life Gets Tee-just, Don’t It
On a Slow Boat to China
Put 'Em in a Box, Tie 'Em with a Ribbon, and Throw ‘Em in the Deep Blue Sea
St. James Infirmary (Louis Armstrong had a hit with this in 1948)
Steppin’ Out with My Baby
The Streets of Laredo
1949
Always True to You in My Fashion
Another Op’nin’, Another Show
Baby, It’s Cold Outside
Bali Ha’i
A Cock-Eyed Optimist
Diamonds Are a Girl’s Best Friend
Did You See Jackie Robinson Hit That Ball?
Happy Talk
I’m Gonna Wash That Man Right Outa My Hair
I’m So Lonesome I Could Cry (Hank Williams)
I’ve Got a Lovely Bunch of Coconuts
Johnson Rag
Mule Train
Red Roses for a Blue Lady
Riders in the Sky (AKA Ghost Riders in the Sky)
Saturday Night Fish Fry (Louis Jordan)
She Wore a Yellow Ribbon (revived that year by the movie of the same name)
Some Enchanted Evening
That Lucky Old Sun
There Is Nothin’ Like a Dame
Too Darn Hot
A Wonderful Guy
You’ve Got to Be Carefully Taught
I’ll post some more titles shortly.
I’m shuddering myself at being in my 80s and everywhere I go that panders to my demographic playing the hell out of some soul pop :rolleyes: <– at marketers not you
Here are some more:
1950:
Adelaide’s Lament
Bewitched, Bothered and Bewildered
Bibbidi-Bobbidi-Boo
C’est Si Bon
Goodnight, Irene
Guys and Dolls
If I Knew You Were Comin’ I’d’ve Baked a Cake
If I Were a Bell
If You’ve Got the Money (I’ve Got the Time)
I’ve Never Been in Love Before
La Vie en Rose
Life Is So Peculiar (Louis Jordan)
Luck Be a Lady
Mona Lisa
Music! Music! Music!
My Time of Day
Rag Mop
Sit Down, You’re Rocking the Boat
So Long, It’s Been Good to Know You
Tennessee Waltz
Tzena, Tzena, Tzena
1951
Blue Velvet (first made popular by Tony Bennett that year)
Cold, Cold Heart (Hank Williams)
Come on-a My House
Hey, Good Lookin’
Hot Rod Race
How High the Moon
In the Cool, Cool, Cool of the Evening
I Whistle a Happy Tune
Kisses Sweeter Than Wine
A Kiss to Build a Dream on
On Top of Old Smoky (the Weavers had a hit with it that year)
Rocket “88”
Shall We Dance?
They Call the Wind Maria
Unforgettable
1952
Bourbon Street Parade
The Glow-Worm (the Mills Brothers revived it that year)
High Noon (Do Not Forsake Me)
Jambalaya
Lullaby of Birdland
Walkin’ My Baby Back Home (Johnny Ray revived it that year)
Wimoweh (The Lion Sleeps Tonight)
Your Cheatin’ Heart
More later. . .
Thanks! 
Continuing:
1953 (This was a bad year for pop music in the U.S.):
Doggie in the Window (I hate this song, but your audience might like it)
Eh, Cumpari!
Hound Dog (the Big Mama Thornton version - Elvis’s version came three years later)
Istanbul (Not Constantinople)
Matilda, Matilda (Harry Belafonte)
Rags to Riches (Tony Bennett)
Stranger in Paradise
That’s Amore
That’s Entertainment
Vaya Con Dios (May God Be with You)
1954 (another thin year):
Fly Me to the Moon (In Other Words)
Hey There (Rosemary Clooney)
Mister Sandman
Misty
Papa Loves Mambo (I hate this one, too, but. . .)
Shake, Rattle and Roll
Sh-Boom (Life Could Be a Dream)
Three Coins in the Fountain
1955:
Ain’t That a Shame
Arrivederci, Roma
Autumn Leaves
The Ballad of Davy Crockett
Black Denim Trousers and Motorcycle Boots
Bo Diddley (by the artist of the same name)
Earth Angel (Will You Be Mine)
Flip Flop and Fly (Big Joe Turner)
Love and Marriage
Love Is a Many-Splendored Thing
Maybellene
Rock Around the Clock
Sixteen Tons
Unchained Melody
The Yellow Rose of Texas
I’ll finish up on the next posting.