The Trans-Siberian orchestra version of Carol of the bells is one of the single greatest goddamn things ever made in the history of humanity and if you disagree I'll punch your dad in the cock

ooo I also want to know

There's a whole bunch of Star Trek versions by the same guy:
https://www.youtube.com/watch?v=3KvWwJ6sh5s
https://www.youtube.com/watch?v=rYUMmIBWm-8
https://www.youtube.com/watch?v=A7s7X9LdNDs
https://www.youtube.com/watch?v=4JDjkUswzvQ
https://www.youtube.com/watch?v=vmrMuwcpKkY

Suzy Eddie Izzard - The Twelve Days of Christmas

twelve monkeys mating, eleven donkeys dancing, ten pygmies farming, nine socks a-swimming... FIIIIIIIIVE GOOOOLD RIIIIIINGS

Also, Murder City Devils - 364 Days

Oh, and Tom Waits - Christmas Card from a Hooker in Minneapolis

I know the second two aren't "classic" songs but they're my favorite Christmas songs.

The silent version of "Last christmas". Way better than the original.

Anything sung by Willie Nelson or Burl Ives. Just dig their voices and phrasing

Heavy Metal band Starkill made a cover of All I Want For Christmas and it's the only Xmas song I listen unironically https://www.youtube.com/watch?v=jz8LpZglKfw

I like this version of Gaudete.

My favorite version of God Rest Ye Merry Gentlemen is the version by The Quiggles which appears on the Nitronic Rush soundtrack.

"First Noel" is an album by Ibrahim Maalouf that has some great jazz versions of well known Christmas music.

it's hard to compete with A Chtistmas Gift for You from Phil Spector, which has to me the definitive versions of a lot of the classics plus one of the all-time greatest tunes period in "Christmas (Baby Please Come Home)." if you like the kind of cheese that sprays out of a can, the Brian Setzer Orchestra does fun rockabilly takes on the classics, and Wizzard's originals "I Wish It Could Be Christmas Everyday" and the other one who's name i can't remember are great. for the nerds in the room, Urizen's "Autonomy" carries on the TSO spirit with a heavy heaping of chiptune, the soundtrack fo the Christmas NiGHTS into Dreams... demo has awesome renditions of the classics in 90s VGM fashion, and look up the demo song on the Yamaha SHS-10 keytar when you get a chance

Wonderful Christmastime 11 hours

No, but seriously, it's really hard for me to pick a single favorite song (or even worse, single best version of a particular song). I do tend to gravitate to the upbeat/rock kinda ones, though: "Need a Little Christmas", "God Rest Ye Merry Gentlemen", " Carol of the Bells," "Sleigh Ride" -- stuff like that.

I will say I recently discovered this song, which I was enjoying during November specifically:

Tom Cardy - Not Quite Almost Christmas Time

Santa Baby by Eartha Kitt, You're A Mean One Mister Grinch (both the 60s version and the Pentatonix version), and a new entrance this year: Where Are You Christmas by The Pretty Reckless (Taylor Momsen, aka Cindy Lou Who, and her rock band)

O holy night is my favourite old Christmas song and this is a banging version of it.

Tommee Proffitt feat. Tauren Wells & SVRCINA https://youtu.be/OsfGJuugPUk

Album: Socks by JD McPherson

Mannheim Steamroller's Up Above the Northern Lights

It's been my favorite Christmas time song forever.

Feliz Bottom Jeans

Home Alone (On the Night Before Christmas)

Home Alone (On The Night Before Christmas) Vol.2

Il est ne, le divin enfant, Annie Lennox - https://www.youtube.com/watch?v=LcJSe0ml5Zo