Sounds like your oven selector switch has failed. My 7 year old model has just done it for the second time. Overheated spade terminals on the live end. Seemingly a design flaw and a £50 spare part.
In an attempt to extend the life of the next switch am ensuring a tight grip on the spade terminal... Quite a satisfying little repair... Otherwise a good oven.
Go safely.
Oly
November 2007