I think people have jumped to an extreme conclusion about how many hate Americans, but obviously there is plenty dislike/hate going around.
America has a 90-year history of fighting communism within and outside their own borders, and this has much to do with why there are prominent numbers of individuals in the Middle East and Latin America who hate us. Especially over the last 40 years, or so, the US provided weapons and support for regimes and dictators who fought communist rule. This is why you might hear that America support Saddam Hussein, who was a rebel at the time attempting a coup, which the US supported.
The Middle East also has a dislike for the US because of the Zionist position of many evangelicals in the country, a group which rose in influence and gained power starting in the 50's, something which is still clearly evident today. I don't actually know a whole lot about the history of the modern state of Israel, but the creation of the new state suddenly legitimized Jewish (and specifically Zionist) agendas over the local Palestinian populace's needs, desires, etc... You have probably seen the effects of this today, as the Israeli state is trying to restrict Palestinian settlement of areas they previously held, which obviously doesn't sit well with the Palestinians.
I'm not sure about this one, but I believe countries like North Korea dislike the US because of the US' brash anti-imperialism which essentially did the same thing as imperialism. Under the -------Act (I can't think of the name at the moment), the US stated that it would defend any country who asserted their own independence in the face of European imperialism. However, through the US' dominance of the global market, they actually created a situation similar to imperialism in which the independent country had to adopt policies that the US would not sanction them for, making them uncompetitive and thus unable to be prosperous. Jamaica, while formerly a British colony, saw this as they had to implement policies which made their own national producers uncompetitive even in their own country, and thus powerless.
The countries which fought this have to assert themselves somehow, and so places like North Korea point out these issues with the world market and America's "forcing" of market capitalism on those countries as reasons not to take part.