Sorry that you're not in agreement...it's hard to have the whole "happy holiday" sentiment when you don't agree on what that means! I dealt with that until this year: my husband is from England and claimed that all this "stuff" was silly and totally American....until our son is old enough to do stuff. Now he's gone crazy: we've had pictures with Santa, he's hurrying me out the door to get my hair cut so we can have family portraits for the Christmas cards, he's got lights on the bushes and house, gone shopping on his own to "study up" on the "good" trees, etc. We've gone to the downtown parade and tree lighting, we're going to ICE and the Polar Express later...All I asked for was for him to take the wreath out of the attic without whining! But I swear before this year, he was a total scrooge.
What we always did (and I would do especially if you have access to a free tree!) is have more than one tree. When I was growing up, we had a lovely tree with the white lights, beautiful crystal or red ornaments, etc in the front room. In our family room, we had the 20 year old, 5-6 foot artificial "Charlie Brown tree" from when I was very small which held the sentimental but not so beautiful ornaments, colored blinking lights, etc. We threw FITS when mom threw that tree out while I was off to college! In the kitchen, mom even had what we jokingly called the Christmas fern (don't know what it was, but it was live and stayed all year) which she would decorate in chili pepper lights, little crawfish, red beans, or rice ornaments, with cotton tufts and dried out spanish moss (we lived in Louisiana obviously). This live "fern" we then turned into a mardi gras tree, a 4th of July tree, a halloween and Thanksgiving tree...
I understand the looking pretty thing, and that's where a pretty tree upstairs would be nice. But as for the cozy hanging out around the house, ESPECIALLY for an elderly family member, I'm all about the simple tree with landmark ornaments like "first christmas", "first home", or handmade stuff. Maybe the "pretty" stuff upstairs and some simple but happy things downstairs would show your husband you're respecting his wishes, but still have your own desires too. If that doesn't work, I'd be all "DUDE-your MOM is 92!" Hope y'all can compromise and enjoy the holidays!