Yes, I know Jesus wasn't born on 12/25 (it was more likely October). I know that early Christians chose to celebrate Christ's birth to coincide with the Solstice celebrations, not only to ease pagans into Christianity but also so they would be less conspicuous (it was a time of persecution).
I see the Father's sending the Son to live among us as being worthy of remembrance. That we do so on an arbitrary day does not matter, after all, the entire calendar is arbitrary as well as pagan in origin. What matters is the remembrance, not the specific day.
For me, celebrating Christmas fills the empty hole that existed for most of the years I was unevenly yoked to my JW ex. I did so throughout my childhood, youth, and early adulthood. I understood the reason for it from the time I was in first grade, thanks to the teachers at our parochial school. To me, the years of ignoring Christmas were years of denying the Father's gift to all mankind. I am not reverting to pagan practices, I am returning to showing appropriate gratitude for God's greatest gift to mankind.
Christmas is not about Santa! See Dicken's Christmas Carol, see Shultz's Charlie Brown Christmas, see the crew of Apollo 8 giving a Christmas Eve reading while voyaging past the moon, see the Salvation Army, USMC, and many others offering charity to whomever is in need. That is the Spirit in action. That is Christmas.
Wishing everybody a "Merry Christmas!",
GL Tirebiter