Is the wife entitled to take her entire salary and save it, and demand that the husband pay all household and children's expenses, knowing that the husband was the one who enabled her to obtain this salary, which is much higher than what she used to earn?

The financial maintenance of the wife and children is obligatory upon the husband. If the money received by the wife is in exchange for a job or a grant from the state, then it is her property, and it is not permissible for anyone to take anything from it. She is not obligated to spend from it on the household unless she does so willingly. The husband is obligated to spend on her even if she is wealthy. The fact that the husband was instrumental in her acquiring this money does not negate her ownership of it, but she should acknowledge his favor. As for saved money, if it is her property, then the ruling is as stated previously; otherwise, she does not have control over it.