The Problem with a list like this might be limiting it to five.....Well, here goes, and in no particular order.
A Christmas Story - There is just very little about this movie that misses. It's great "kid-think" all the way through. One of the kind of "subtle things" is how, through-out the movie you see the parents as these "bickering, shouting, caricatures - in their relationship with each other, at the end, in their one scene without the kids and in front of the window fo the darkened room, they are gentle and loving with each other.
A Christmas Carol with George S Scott - In my opinion the best version by far. Who better to play Scrooge than Scott. Henry Winkler did a version called "An American Christmas Carol" set in the depression era that is also quite good.
It's a Wonderful Life - A cliche perhaps but really what a great movie to show true blessings, and a terrific cast.
White Christmas - Silly improbable and all of that, but who cares. It's got Bing Crosby and Danny Kaye in it. I love the exchange between them when they are getting off the train in Vermont. Comic timing at it's best. Also some wonderful Irving Berlin songs and great dancing.
The Bells of St Mary's - Not a "Christmas movie" per se, but a good movie and there is a great scene in it where the first graders are rehearsing a Christmas play. You can watch it on YouTube here
While You Were Sleeping - Great Story about family, Love Sandra Bullock and Jeff Daniels together.
Not sure if I can classify these as "favorite Chrismas movies" but...Hallmark channel has been running a bunch of Christmas movies this year and while they are all pretty "formulaic", there are a couple of two or three that stand out.
*The Christmas Card - I like it because the lead gal is pretty but also "real" looking and the Characters are (for the most part) not "cardboardy". It's a family and a story that one can identify with.
*The Most Wonderful time of the Year - It's got Henry Winkler in it - and is just plain funny while poking fun at all the artifical garbage that people put on Christmas.
*A Time for Miracles - Again, good acting and characters that are "real", by that I mean they aren't "supermodel" types so much as they are actors.
Then there are Christmas Specials -
I was there when two of the most popular debuted in 1965, A Charlie Brown Christmas, and Rudolph the Red Nosed Reindeer. Still love em. Yukon Cornelius and Hermie the elf....Lucy and Linus and the gang.
Also love "How the Grinch Stole Christmas"
Don't know if I have five, I'm not that much of a movie watcher. But I have to throw out there:
1. It's a wonderful life - Such a good movie about the real value of life & family - even when it doesn't feel that way. (this is also the classic that the Home Alone family was watching while in France in that movie)
2. Jingle all the way - How can you go wrong with Arnold Schwarzenegger saving Christmas? I love this movie. Again the realization of an over-busy father that his family is more important to him than anything else. I love the way the movie doesn't take itself seriously so the slapstic can really hit home.
I like the a lot of the ones already mentioned (Elf, Christmas Vacation, A Christmas Story, While You Were Sleeping, etc), but thought I'd list five that are not already mentioned.
Ben Afleck in Surviving Christmas(comes on TBS & TBSHD 12/4 at 11am, so set up your PVRs!)
Loretta Switt in Best Christmas Pageant Ever (available as a short audiobook as well, but hasn't been on the air in years)
Bill Murry in Scrooged Gremlins Trading Places