I know this won't help much, but mediate with the old mummy mantra
@it is only a stage, it is only a stage, it is only a stage'
Then get a huge glass of wine and chill for a bit
Seriously IMHO under 5 is too young for the pasta jar, they don't really understand the build up to a reward type thing for good behaviour and taking away for bad behaviour. It is instant gratification or noting. In some ways I like the idea of swapping pasta for chocoltae, eg if you are naughty mummy gets one of your buttons, however they still don't really have that concept of time.
Time out is not just a punishment for your child, it is TIME OUT for both of you. So if they do play in their rooms, fine, at least they are not winding your up and you geteh chance to calm down.
My kids obey me now (most of the time) and yes I have smacked, didn't work for dd2, worked on dd1. Time out, worked on DD2, not on DD1???
However the thing that worked the best was taking something away that is precious to them. eg their fave barbie. Take it away, let them see you give it to a charity shop, see you mean it. That is VITAL that and consistancy. I started a thread recently about ripping heads of barbies or threatening to burn fave toys! I was a joke with my kids, but underneath it all, they believe I will do it. They remember me taking something away they liked!!