The best is a little village in Scotland called New Galloway, not far from Castle Douglas. Some of my most peaceful and fulfilled moments of my life have been spent there, working on a little farm. I think I'll become a farmer once I get some money stashed away, it's a hard life but if you can keep your head above water, it's very rewarding.
Not sure of the worst, as every place has its charm. Maybe Tenerife or any place abroad where the 'British invasion' has happened. I go abroad for new experiences, not to read the Sun, drink Carling and have a full English every morning. Despite this though, as I said, it does have some charm to it.