They're uncomfortable around Hitler. Other than that, I'm not much of an expert.
I know Jewish people who totally embrace Christmas, and I know Jewish people who rock the shit out of Hanukkah, but I've never once got the sense that they were uncomfortable. Almost no one I've ever met puts any religious significance on the holiday, if that's what you're getting at. Jesus isn't relevant to my Christmas, so why would he be relevant to theirs?
Quite simply, if I went to a house at Christmas time, and they had a dead dog hanging from a coat rack and the floor was covered in chicken stock powder, and they said 'Merry Christmas' at the door, I'd be like, whatever.
To each his own. Religions and cultures and beliefs don't have to make you into a hateful, scaredy douche around the holidays. That's a choice, like murder and supporting boy bands.
Short Answer: I've seriously never met anyone, not of any creed or color, that is pissy about people having a good time around the holidays in whatever way makes them happy. Oh. Expect hard-core atheists. They don't like the Christ in Christmas at all. Ask them about it; you'll see.