ok now I just selected all objects and "break lights links"

And that makes my rogue light turn off...but also kills ALL my other lights....buh!!

EDIT: I figured out the rogue light... aperantly the lights on my bilboard were somehow bouncing off the bilboard and it was acting like a super reflector or somthing....either way i have to figure out how to light my bilboards without i them illuminating the whole scene...