Engine won't turn off/Brakes funny

[356nen]

Hey Guys,
Well after about a month of ownership I am now starting to have problems. This morning driving to work my brakes started to act funny. Sometimes they would act normal and other times the pedal was extremely stiff. I would press down hard on the pedal and it would have very little to no movement. The car was extremely slow to brake and it was a bit scarey. So, when I get to work I pop the hood thinking some kind of vacuum line had come undone but could not see anything wrong. When I got to kill the engine it will not turn off. I remember reading something about it a switch to kill the engine but could not see any switches. How do you turn off the engine, I do not have the car manual? I panic but by moving one of the pump rods got the car to turn off. Can someone point me in the direction where to look for?
Is it just a vacuum leak. How is the brakes and the engine not turning off related.
Thanks.
rene