According to the UN Development Program's Human Development Index, the best place in the world is Iceland. Or, at least, it's the place with the best human development. People who love warm weather wouldn't actually enjoy Iceland very much. I'm not one of those people and I had tons of fun during my stay in Iceland (see my many photosets of the trip up on my Flickr) and they certainly seemed to enjoy a very high level of human development. As a general matter, I would recommend to all countries that they locate themselves near a limitless supply of geothermal energy since this makes it pretty easy to combine prosperity with environmental soundness. In general, though, the combination of a fairly open economy and a fairly flexible labor market with a strong welfare state and a commitment to high-quality public services works very well in Iceland, Norway, Denmark, and the Netherlands and I think we'll see both the US and countries like France and German move closer to that model in years to come. \
Kate Sheppard, meanwhile, points out that the Nordics also dominate the Humanitarian Response Index. Since the world does need military power to provide certain kinds of global public goods and militaries show real economies of scale, I don't think the US should aspire to actually match the smaller European countries' commitment to aid in share of GDP terms (it's also plausible that small countries' aid programs are more effective since they're less geopolitically fraught; nobody worries about Denmark's efforts to rule the world), but we do need to rebalance our priorities somewhat.
Photo by me, available under Creative Commons license