The only reason I could leave Canada would be for my dream job....but since I cannot really even define that, I am not sure I will even entertain it. I live in my hometown, mainly because I am around to look after my aging parents who have no other family left near to them. Had I the chance to emigrate, I would be doing it knowing what I was leaving my folks to. It would be emotionally tough.
As far as other nations are concerned, I have been all over North America, but really compared to Europe, that isn't well travelled. Then again, I have seen enough of other cultures through the immigrants that I can deduce where I might LIKE to live or not.
If I was emigrating to Europe, I think Germany, Ireland or the UK would be my choices, although I must admit, Spain would be looked at. If I was looking at any other place, Australia and/or New Zealand would be my only other viable options. My ability to mangle any language other than my own pretty much would hem me into English speaking nations.
Right now, looking at a -5 with -20 C windchill, Hawaii is looking REALLY good....