I am the opposite of you, I grew up in a household where Christmas morning meant the kids rushing out to the tree to see all the gifts that Santa brought. Even when we were older and Santa was more of an idea than something we really believed in, there were still plenty of gifts under the tree. And full stockings. Plus I had two sets of grandparents and many Aunts and Uncles that would always give a little something. We weren't rich, just regular middle class Americans, but Christmas was like this for us and many of my friends. My husband's family growing up did not have a lot of money, and with 4 kids, they were probably lucky to get one gift each. They did not have grandparents nearby (they lived in Mexico) nor much other extended family that would buy for them either.
This will be the first Christmas that we are buying "presents" for our son. Santa hasn't come into play yet because he's barely one year old and doesn't understand that yet. It's actually not something my husband and I have really sat down and talked about, his expectations vs. mine regarding what Christmas should be for our family. He and I haven't really bought gifts for each other for the past few years because we haven't got the money. Since our son is so young, he won't be getting a lot, a few puzzles, some walking toys, things I want him to have and would have purchased for him anyways.
You and your husband need to come to a compromise on this. If money is an issue because of your recent home purchase, make sure he is realistic about that. Write out a budget, and include Christmas in it. I think you should get some gifts for your kids, but they don't need everything on their "list", just a few special things that fit into your budget. Christmas can be special without lavishing the kids with a ton of "stuff." And it's definitely not something you should go into debt over. Don't make it an issue to your kids, don't expect them to be disappointed with less. They read into your attitudes and expectations, and react accordingly. If they do come out of Christmas morning disappointed, then you can explain that your new house was a present to the entire family this year.
To get your kids involved in charity, you could all volunteer some time at a food pantry or soup kitchen. Get them to inventory all their toys and games and donate unused or outgrown things. Take them to the toy store and let them pick out something to give to toys for tots. The possibilites are endless, but try involving them in the decision of where and how to give of themselves and they might be more willing to actually do it. Kids, even "spoiled" kids, can be amazingly generous when given the opportunity.
Good luck and Merry Christmas!