There was one ep when Kelly was going out with this older man and Hayden disapproved. They got into an arguement and Hayden said "Christine open a window I'm going to jump!". Kelly then said "I'll open it, which one?". No one thought to call the suicide hotline. Homicidal talk came in one ep where Hayden's exwife kept talking of how she should have killed Hayden years earlier as he was not showing up at his daughter's wedding.

I think these were just figures of speech that you hear on most sitcoms, and in real life sometimes.