The decorations is all a matter of culture and tradition. The true meaning of the holiday is the birth of Christ and God sending His Son.
It's a tough one to figure out though because I find myself having to constantly remind my children what the REAL reason for Christmas is while I am in the midst of buying massive gifts and running around like a chicken with my head cut off.
I've personally scaled WAY back on all this. We didn't even put up a tree this year. I put out a few things around the house to make it more festive but never got a tree. Partly because our apt is sooooo small and now we have 4 kids in here. yikes....it's crowded.