You have made a wiring error - when the light is switched OFF the light comes on and when you put the switch to the ON position it connects live to neutral with no load between them - a short circuit - the fuse /breaker prevents the wires from melting and a fire breaking out and the house burning down - which is good.
This link below has a picture that may help you - if it's too much for you then call in a sparky...
http://www.flameport.com/electric/lighting_circuits/lighting_ceiling_rose_looped.cs4
Notice that NONE of the live wires connect to the light - only switched live (it looks like a neutral) and this is your error.
Good luck...
Peccavi
August 2010
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