My iphone4 got into SIRI now it can't login, won't regognize my passcode it just talks to me.

My iphone got into SIRI, now all that works is a stupid voice telling me the content of my home screen, date, time, slide to open etc. Nothing else works and it will not recognize my passcode. It looks like the software had screwed up and got a mind (and voice) of its own.