Originally posted by mikelomIceland is the only European country which does not have summer time: http://en.wikipedia.org/wiki/European_Summer_Time
Halloween originated in the uk after its idea was passed to us from the Romans.... it was then passed to you. It is still celebrated here very much. DST was first practised by the germans in WW1 closely followed by the UK, except we kept it and most of europe now does not practise it. Sweden also changes the hour I think.
Edit:spelling
England and Ireland used to change the clock on a different date than the rest of Europe, but now it's the same date in all European countries (but not the same as in the US).