Either somewhere beautiful like a quiet neighbourhood in New England, USA (especially in the autumn) or somewhere in the forests or near the mountains in Germany (i.e. the Bavarian Alps)
If I had to stay in the UK, I'd like to live on the outskirts of London.
London. Big, busy, full of life. I'm such a city person.
Amsterdam is my 2nd choice. It's much smaller but the atmosphere and mentality are worth it. Plus it's a beautiful country, quite wealthy, so living conditions are good.