Nothing. ********* has no significance to Jews, Orthodox or not. There is a modern secular Jewish tradition to eat (kosher) Chinese food on ********* and to go to movies. There is an older tradition that marks ********* Eve as Nittel Nacht, during which Torah study is avoided in favor of pointless activities such as playing cards. The Talmud forbids (in tractate Avodah Zarah) forbids even the appearance of honoring idolatrous festivals or contributing to their observance. Christianity is not classified as being idolatrous, but there are a sufficient number of problematic Christian practices (and even more problematic beliefs) that many of these prohibitions apply, at least in part.