Just because you want to hear Christmas music doesn't mean you have to turn off the classic rock. There are a number of good (i.e., before 1995) artists who have put together interesting renditions of Christmas classic or new and unique Christmas music.
There are a number of compilation albums out there that feature the sounds of different classic artists performing Christmas songs. This one does feature Bryan Adams on one track, but it is nonetheless an interesting collection of artists like Elton John and Joey Ramone performing Christmas-themed songs.
An incredibly strange classic rock Christmas album can be found in this collection. If you will notice the track listing, Father Guido Sarducci is featured on this album alongside Styx and REO Speedwagon, among others.
For a classic sound that mixes rock, jazz and other sounds, try this album. It's one that can be listened to all year long, and it appeals to kids as well as adults.