I think DD started being like that when she was about 1 too. I couldn't stand her, really got so sick of her. She was just ALWAYS doing things that required me to stop her, just like what you were sayign about reaching for knives etc. SO frustrating, she was aconstantly screaming and crying and I have so little patience, I used to just lie on on the floor covering my ears.. then she would attack me with her claws and i'd just curl up in foetal position.
Certainly not what you should do! Now she is a few months older and I think i've become desensitized to her screaming. When she gets all angry like taht for a silly reason I completely ignore her. Sometimes I go into my bedroom and shut the door! I don't know if it's the right thing to do, but when I do it she stops crying not long after, even ends up playing happily by herself.
There's a few threads on here about dealing with tantrums, people had some really good advice and techniques.
Hope you find a solution soon, I know how annoying it is when they just won't let go of your legs..