I have half my family in the USA, half in Canada. I have a cottage on the border, and each weekend will have been in both countries several times. The two countries are very similar, and yet, quite different. Of course, both countries are very large, and regional differences are greater than the country differences. The USA is traditionally more of a melting pot of immigrants, whereas in Canada the immigrants tend to retain their identity longer. Medical care is excellent in both countries, but in the USA it's more easily available to those with money, whereas in Canada everyone has access, but waiting times can be a real pain (both figuratively and literally). I have met "ugly" Americans and I have met "ugly" Canadians (and also "ugly" Quebecers). No place has a monopoly on ignorance and bad manners. The USA is a more militerised country than Canada and that is visible in the culture and in the number of people who are associated with the military in one way or another. Economically, there has traditionally been more opportunity in the USA than Canada, which is not too surprising when the USA is ten times bigger then Canada by population. The political class in either country isn't much to be proud of. Canadians tend to be more aware of things going on outside their borders than do Americans, but then again, I've met many Americans whose awareness of world events and cultures would put many Canadians to shame. Weatherwise, the south part of the west coast of Canada (as in Victoria and Vancouver) have very nice climate, as does the Niagara region. Winters in Canada, from the Rockies to the East coast basically suck unless you're into winter sports.
Marija, where you live in either the USA or Canada may be a more important factor than which country you decide to go to.