Is there any issue with doing business with non-Jews In the around Halloween or Christmas?

Shalom, Thank you for your question. The issue of doing business with idol worshippers on (and on the days preceding) their festivals, is mentioned in the Mishna and Gemera, as well as being addressed in the classical Halachic works. On a practical level – today the accepted halachic ruling is that we allow doing business with non-Jews even on their holidays. Several different reasons are given for this, including the different types of non-Jewish worship today, also issues of animosity, and what was included in the original decree. (See the Mishnah Mesechet Avodah Zarah 1:3, Rambam Hilchot Avodah Zarah 9:1, Shulchan Aruch Y.D. 148, Igrot Moshe Y.D. 1:71.) Blessings.