Jews and Muslims wouldn't have the same theological basis as Christians for celebrating the birth of Jesus. But is that really so important?
Whatever else Jesus was or was not, he certainly was one of Israel's greatest prophets. Surely the Abrahamic faiths (and perhaps others as well) can agree that, in some sense, God was at work in Jesus' birth.
We should focus on that common ground we share, instead of on the theological speculations that we allow to divide us.
Christmas should be an occasion for all theists to celebrate God's work, in fellowship with each other.
So, Cindy Chupack, don't feel one bit guilty about putting up a Christmas tree in your Jewish home, in praise of the Creator.