Merry Christmas

My opinion is that it doesn't matter either way. However, I prefer to say Merry Christmas. I don't personally know anyone who doesn't celebrate Christmas, but if I did I wouldn't think it should offend them if I said Merry Christmas. Likewise, if they wished me a Happy Chanuka, I would smile and say thank you. It's not a big deal. Everyone has different beliefs and if people aren't tolerant of other people's beliefs then they are just selfish and not a very well-rounded person.