Scholarly disagreement

As-salamu`alaykum. I have been following Islam since 2006 and I thank Allah for guiding me to the right path. But I am confused with hadiths. I understand the Qur'an can never be surpassed by hadiths as the latter were written 200 years after Prophet Muhammad (peace and blessings be upon him). And I also know scholars have spent many years taking care of avoiding fabricated hadiths. But there are arguments among Muslim scholars regarding many issues, so I'm confused whether to believe in hadiths or not. What should I do to avoid confusion?thanks in advance.

Dear scholars, As-Salaam `Alaykum. There are nowadays some people who claim knowledge and attack great scholars, brandishing them as a bunch of hypocrites who issue Fatwas just to please the rulers. What do you think of this slanderous remarks? Jazakum Allah khayran.

Is it true that jurisprudential disagreement among scholars is a kind of mercy to laymen? If so, how come?