If ever there were one album that one could listen to, it would most certainly be Sgt. Pepper's. Any and all styles of Beatles music are featured on this masterpiece. Quick and exciting (Sgt Peppers, Good Morning, Good Morning, Sgt Pepper's Reprise, Getting Better, Lovely Rita), beautiful and mystifying (She's Leaving Home, When I'm 64, A Day in the Life), experiments in song (Within You Without You, Mr. Kite, Lucy in the Sky with Diamonds), soul-esque (Fixing a Hole, With a Little Help From my Friends). Paul McCartney's virtuosity and versatility in all music is expressed immensely, John Lennon's work is exceptional as well (especially some of his vocals), George Harrison showed his turn to Indian music with Within You WIthout You while still managing to keep his general mastery of the guitar, and Ringo Starr creates his best song with the group (With a Little Help From my Friends). Excellent performance all around. I also suggest The Beatles 1, Rubber Soul, and The Beatles (White Album).
What's great about it: All of the songs, the remastery, and the Beatles
In my opinion the 2nd best Beatles album and 2nd best album of all time, Rubber Soul has seemingly endless playback. It expands upon soundscapes of rock (Drive my Car, Run for your life), simple yet haunting tunes (Michelle, Girl), and some songs that just leave everyone breathless (In my Life, You Won't See Me). From the up-beat solo of drive my car to the beautifully set harmonies of Girl the album never ceases to impress and belongs in every Beatles fan, no, every music-lover's library.
What's great about it: The songs themselves, the remastery of them
What's not so great: Semi-paranoid fear of damage because it is such an excellent album