Here's a list of known Christmas Cards for DOS Computers:
Houston Graphics 1991[archive.org]
Enlighten 1992[archive.org]
Systemax 1992[archive.org]
MicroProse Christmas 1993[archive.org]
MicroProse Christmas 1994[archive.org]
Night Before Christmas PC Life 1987[archive.org]
IBM Chaplin Christmas 1985[archive.org]
Big Blue Disk Issue 50 1990[archive.org]
Sierra Computer Christmas 1986[archive.org]
Sierra Computer Christmas 1988[archive.org]
Sierra Seasoned Professional 1990 16-Color[archive.org]
Sierra Seasoned Professional 1990 256-Color[archive.org]
Sierra Computer Christmas 1992[archive.org]
Jingle Disk 1986[dosgamezone.com]
Shareware Frostbite Xmas Card[archive.org]

Other Notable Cards:
Christmas Demo (Scott Haag, 1997)
Jingle Disk (Thoughtware, 1985)
A Tandy Bear Christmas (Radio Shack, 1987)
Electronic Christmas Card (Paul F. Allen Jr. / Softdisk, 1988)
A Holiday Greeting (Animotion Graphics, 1989)
The Christmas Sing-Along (Intra, 1996)

https://www.youtube.com/watch?v=R0yukAT3Rew
These Christmas Cards were shown on Computer Displays in stores as a self-running slide show of pictures with musical accompaniment.

1. Create a New Folder in your Stargunner Directory and name it XMAS.

2. Download the Christmas Cards for MS-DOS then extract to the Following Folders in the XMAS Folder once you make them
Houston Graphics 1991 = HGX91
Enlighten 1992 = ELX92
Systemax 1992 = GREET92
MicroProse Christmas 1993 = MPX93
MicroProse Christmas 1994 = MPX94
Night Before Christmas PC Life 1987 = IBMX87
IBM Chaplin Christmas 1985 = IBMX85
Big Blue Disk Issue 50 1990 = BBD50
Sierra Computer Christmas 1986 = SXMAS86
Sierra Computer Christmas 1988 = SXMAS88
Sierra Seasoned Professional 1990 16-Color = XSP16
Sierra Seasoned Professional 1990 256-Color = XSP256
Sierra Computer Christmas 1992 = SXMAS92
Jingle Disk 1986 = JINGLE86 (NOT Compatible)
Jingle Disk 1985 = JINGLE85 (NOT Compatible)
Shareware Frostbyte Xmas = SFBXMAS

3. Run the desired Christmas Card in DOSBox's XMAS Directory.
Runtime File List:
Houston Graphics 1991 = XMASCARD
Enlighten 1992 = ENLCARD
Systemax 1992 = GREET
MicroProse Christmas 1993 = XMAS
MicroProse Christmas 1994 = XMAS
Sierra Computer Christmas 1986 = CARD
Sierra Computer Christmas 1988 = XMAS
Sierra Seasoned Professional 1990 16-Color = SIERRA
Sierra Seasoned Professional 1990 256-Color = SIERRA
Sierra Computer Christmas 1992 = SIERRA
Shareware Frostbyte Xmas = CARD
Night Before Christmas PC Life 1987 = XMAS

Big Blue Disk Issue 50 1990 = GO (From the Issue 50 Menu, select Electronic Christmas Card then select "Run It")

4. Have a Very Merry Christmas & a Happy New Year!

IBM Night Before Christmas 1986
= Press CTRL+ALT+S to disable Sound & Music