To be perfectly honest, it all depends on what mood I am in when it comes time to decorate the tree.
I have multiple boxes of different ornaments.
First, I have the "blue and silver" box. It has blue and white lights, blue, silver and white ornaments (of any kind), blue bows and both a silver star topper and a big blue bow/ribbon topper (again, depends on the mood!). That is what I have up this year.
I also have a "red and gold" box. Same as the blue and silver box, except red and gold, lights are, believe it or not, red and white!!! I had a weirdo idea for decorations that year!!!
Then, I have the "green and red" box, again, same as blue and silver, just green and red.
I also have a small box of pink and white ornaments, which can be used on a very small tree. DD was born 2.5 weeks before Christmas and DH set up a tree in our bedroom while I was in the hospital. It was pink and white to commemorate DD's birth. That is also where the "Baby's First Christmas" ornament is! When we put up the "traditional" tree, we use the decorations on it sometimes.
And finally, I have the traditional box, it has all of my oldest ornaments (passed down), DH's (very few) passed down ornaments, ornaments that we have bought here and there on vacations and such and all of DD's crafty ornaments. This one gets used the most, but sometimes, I just want something a little more "perfect"!