I would just caution you on bringing friends at that time of year. People who don't own at
DVC vacation differently than those who do. We just took our dd best friend and their family in April. They just about wore me out!!! They were up early to do every early entry they could, and didn't want to go back to the room until the parks closed.
Now, my dd and I got a "virus" (we always seem to catch one) and we were EXHAUSTED (seriously, she slept in her stroller a lot, and I would fall asleep on rides). Our friends caught the virus as well, but it did not hit them until they got home. My friend sent me a note explaining what a great friend I was, because is she felt as tired at WDW as she felt the week after, she would've "ditched" me in a heartbeat!!!

But, I really wanted the girls to spend time together...and, honestly....you're so tired in WDW...who can tell what's "sick" and what's just being tired (and getting old)!!
Anyway....my point is this....we have only been DVC members for a year, but already it has changed the way we vacation. We now have kind of a "We'll get there....sometime today...." attitude. Our friends looked at us like we were crazy...afterall, they were on a "Once every 5 years WDW vacation"....they wanted to go..go...go!!! I used to be that way until we bought into DVC.
But, at Christmas and NY's....that is a REALLY bad time to take people who do not make a "yearly pilgrimage" out of the event. Although we have not been in WDW on Christmas, we have been in DL on Christmas...and, let me tell you...it was CRAZY!!!!! DL "fast passes" IASW because the re-do it for the holidays. Fast passes for the day were gone before noon, and the crowds made walking thru the park similar to standing at a rock concert. It took us two hours to walk from the front gate to IASW to retrieve our fastpass for 9:00PM (this was 10 in the morning). Every line for every ride was a minimum 3 hr wait. So, we left....went to the Grand Californian...hung out and had a wonderful lunch. We got back into the park around 3 pm, made it back over to IASW by 5pm (another 2 hr walk) and immediately got a spot for the 7pm parade (although we were NOT able to get a front row spot...those had been taken since about noon....people just kept the same spot they had from the 3pm parade). We saw the 7pm parade, got in line for IASW (the fastpass line was over 2hrs long). Got out of IASW by 9:45, and made our way to the front gate (it took about an hour). So, in the course of the day, we rode IASW once and watched one parade....and, it took our whole day.
It was fine, but certainly not your ideal DL trip. I would hate for your friends to experience anything along the same lines and have them think "that" is WDW. People can also get very frustrated with crowds. If your friends are VERY frequent travelers to WDW (or, as you live in CA...if they've ever been to DL on Christmas Day) they would probably be okay...I just wanted to "warn" you a bit. Traveling with friends can always be a little "tricky"....traveling with friends at Christmas has the potential to be insane!!
Beca