I know many will hate them but mostly because of events in my life that I associate with them, I will forever love the following songs;
Rebel, Rebel by Bowie
Hotel California by The Eagles
Boys Of Summer by Don Henly (?)
Don’t Fear The Reaper by Blue Oyster Cult
The Fire Down Below by Bob Seeger
There are others, maybe I’ll post them as I remember.
Lola, by the Kinks. I’ve heard it a bajillion times but it’s still pretty good.
Separate Ways by Journey.
Roll With the Changes by REO Speedwagon.
Her Strut and Hollywood Nights by Bob Seger.
Born to Run - Bruce Springsteen
From the first notes, the volume gets cranked to max.
I Don’t Need No Doctor – Humble Pie live
Honky Tonk Woman - Stones
Roadhouse Blues - The Doors
Almost anything by The Who
Long Cool Woman, The Hollies
My Sharona, The Knack
Hey Nineteen, Steely Dan
Everybody Wants to Rule the World, Tears For Fears
Holding Back the Years, Simply Red
The Air That I Breathe, Simply Red
I’m Not In Love, 10CC
Too many to list, really, but those make me reach for the knob every time.
I pretty much listen to everything at FULL FUCKING VOLUME. Its nice to live in the middle of nowhere and few neighbors.
Boston (whole first album) and Pink Floyd (Wish You Were Here, Dark Side, Animals) never get old. I’ve actually worn out a couple CD’s.
When my wife leaves the house, the volume goes up!
Oh, yeah, and no matter where I am or what I’m doing, whenever Ronnie tells me to “Turn it Up!” at the beginning of “Sweet Home Alabama”, I do. It’s like a game to me now.
I dunno if it fits your definition of classic rock, but “War Pigs” by Sabbath will always put my speakers in danger.
And still as intense and relevant as it was all those years ago
“Lights,” by Journey. I’ve really come to like it. And it’s set in San Francisco. 
Evil Woman - ELO
Money - Pink Floyd (although the 7/4 time sig makes me feel I’m stumbling if I’m walking thru the house)
Aqualung by Jethro Tull
Room to Move, John Mayall
These Dreams by Heart and Kyrea (sp?) by Mr. Mister take me back to a very bittersweet time in my life so I’ll usually crank those up too.
Running With The Devil by Van Halen takes me back to a really happy place!
Not mainstream enough to qualify as “classic rock” but I love the artist and song so I’ll allow!
= )
Holding Back The Years is so great, one of my favorites.
Hair of the Dog - Nazareth
Layla - Derek and the Dominos
Most Rolling Stones
Anything Janis Joplin
Why yes, I am old. Why do you ask?