Thanks all for the input and detailed understandable explanations on "spin" and the advantages of interrupt, points taken. Dont really like asking so much but cannot think of any other way!
It's been suggested that one way of dealing with switch bounce if using interrupt is to add detachinterrupt to the code but there must be a catch as its never been mentioned?
Only previous programming experience is with picaxe but that has an excellent simulator to help which I miss but its all good experience especially with the vast amounts of Arduino info out there.
Peter