Probably Sweden, because of the hot chicks, and the fact that everything over there is so damn logical.
Scotland might be nice too, if I've got the money to just park my ass in a house in the Highlands, writing and reading and drinking whiskey all day and bagging some monroes now and then, without actually having to look for a job. It's a beautiful country, and I've got family there, so that's a plus.
I would like to spend a serious amount of time in the USA though. Everything over here is simply soaked in American culture, but I don't actually know the country. We Europeans tend to stereotype Americans as loud, obnoxious and dumb, but every American I've ever met in my travels has been the exact opposite of that. I feel like the USA is a tiny little part of me, yet I've never actually been there.