Welcome
Well, you have a lot to work out there, but maybe if I can tell you why I celebrate christmas now, it will help you.
First, we all know the reason JW don't celebrate christmas, and all it's "pagan" origins. But when it gets down to it, does it really matter where something came from? I honestly believe it doesn't. I think what matters is how you use it, and what it means to you.
Pagans long dead have no influence over me, people alive today have little to no influence over me. So why should there choices, and there ideas change the meaning I put into what I do today? This argument can go for or against christmas actually. Why should you follow a tradition just because others do it.
Well, for me, it's a matter of deciding what Christmas means to me. It's a time to be giving, and a time to appreciate everything you've been given. It's a time to gather together, love one another, and be happy about life and it's meaning.
Why do it on a specific day? Well, for one, it's really hard to do something right if you don't plan for it. Secondly, why not? If we throw off the chains others have placed on it, what is wrong with it? What's wrong with sharing a good feeling with those around you? There is a common good-will present in many people around that time, it's a good thing.