Only in Israel can the Attorney General say that from a legal standpoint Deri can be a Minister but he will have a hard time defending it

What on earth does that mean? If legally Aryeh Deri can be appointed a minister (he fulfils all of the criteria set out in the law), what is there to defend? It is an open and shut case. The answer is that the Supreme Court in Israel has decided that it has the last word on judgement, and therefore if in the Supreme Court's judgement he is not "worthy" to be a Minister, then he can't be appointed.

There is no way to describe this except as judicial dictatorship. The elected government makes a decision based on their judgment of what is best and comes the Supreme Court and substitutes it's judgment and says that the decision was unreasonable. Why should the opinion of unelected judges hold more weight then the man elected and charged with the responsibility?

One of the fundamentals of representative democracy is that the people elect representatives who are supposed to use their judgment in running the government. Basically what the petitioners are saying is that based on our judgment we think he is a bad candidate and we would not have appointed him. The problem is that Netanyhau was elected to apply his judgment as to what is best, not you, and not the Supreme Court, if you don't like it run for the Knesset.