Boy this is gonna be a long list. Haha
All of The Mamas & The Papas albums, but "If You Can Believe Your Eyes and Ears" and "The Papas & The Mamas" in particular.
All of ABBAs albums, with "Arrival", "The Album" and "Super Trouper" being probably my most listened too.
The Kinks - Face to Face, The Kinks Are The Village Green Preservation Society, Something Else, The Kink Kontroversy.
The Zombies - Odessey and Oracle, Begin Here
The Monkees - The Birds, The Bees & The Monkees, Headquarters, and Pisces, Aquarius, Capricorn & Jones Ltd. Love all their albums though even the earlier stuff.
The Beach Boys - Pet Sounds, 20/20, Sunflower, Summer Days (and Summer Nights), Wild Honey, Friends
George Harrison - All Things Must Pass (one of my all-time favorite albums)
Cream - Wheels of Fire, Disraeli Gears, Fresh Cream
The Doors - The Doors, Strange Days, LA Woman, Morrison Hotel
The Beatles - Rubber Soul, Magical Mystery Tour, Revolver, Abbey Road
Black Sabbath - Sabbath Bloody Sabbath, Vol 4
Jefferson Airplane - Surrealistic Pillow, Crown of Creation, Jefferson Airplane takes off, After Bathing at Baxters, Volunteers
Iron Butterfly - Heavy, In-A-Gadda-Da-Vida, Ball
Sam & Dave - Soul Men, Hold On, I'm Comin'
Martha Reeves & The Vandellas - Dance Party, Heat Wave
The Supremes - Where Did Our Love Go, More Hits by The Supremes, The Supremes Sing Holland, The Supremes A Go-Go
The Byrds - Younger Than Yesterday, The Notorious Byrd Brothers, Fifth Dimension.
The Box Tops - Dimensions, Nonstop
Nancy Sinatra and Lee Hazlewood - Nancy & Lee
Buffalo Springfield - Buffalo Springfield, Buffalo Springfield Again, Last Time Around
Bee Gees - Horizontal
The Yellow Balloon - The Yellow Balloon
The Cryan Shames - Scratch in the Sky
The Peppermint Rainbow - Will You Be Staying After Sunday
Shocking Blue - At Home, Scorpio's Dance
Grapefruit - Around Grapefruit
The CA Quintet - Trip Thru Hell
The Association - Insight Out
The Electric Prunes - Electric Prunes
The David - Another Day, Another Lifetime
The Cowsills - The Cowsills, We Can Fly
Sagittarius - Present Tense
The Turtles - Battle of the Bands, Happy Together
The Idle Race - The Idle Race, The Birthday Party
Donovan - The Hurdy Gurdy Man, Sunshine Superman
The West Coast Pop Art Experimental Band - Part One, A Child's Guide to Good and Evil
Hawkwind - Space Ritual
Camel - Mirage
Judas Priest - Screaming for Vengeance, Defenders of the Faith
Pet Shop Boys - Actually, Please
Oasis - What's the Story (Morning Glory), Definitely Maybe
Boston - Boston
Fleetwood Mac - Rumours
There are a hundreds of other albums I could list but I'll stop at that. Also sorry if I spelt any of the titles wrong.