[Constitution 123]

I am not very good at “lawyer talk” so forgive me if I use the wrong words. However, for the sake of this conversation, I will assume for the moment you are correct and that the ultimate remedy (the removal from office), can only be accomplished by congress. But what prevents the courts from hearing the case, coming to a conclusion based on LAW and forwarding their findings to congress for action? If congress fails to act, then we know where to focus the blame. But if the courts fail to act, they also shoulder the blame. I do not expect much from the currupt congress until there is a court case that forces them to act.

[Nero Germanicus]

That’s an excellent question and the answer is “NOTHING.” Both the Nixon Articles of Impeachment drawn up by the House Judiciary Committee and the Clinton Articles of Impeachment relied heavily on evidence produced by the Watergate and Whitewater & Paula Jones Grand Juries.
What hasn’t happened with Obama is a CRIMINAL investigation by a grand jury that would set the stage for a finding of probable cause of high crimes and misdemeanors having been committed.
Also, it is likely that the other option for removing a president, resignation would come into play if there were to be a criminal indictment. Nixon resigned after being named by the grand jury as an “un-indicted co-conspirator.”

[Lurking Libertarian]

But what prevents the courts from hearing the case, coming to a conclusion based on LAW and forwarding their findings to congress for action?

Because courts hear cases, which means that the courts can decide legal issues only in the context of resolving a dispute between two parties that the court can remedy. Since the administration of George Washington (literally), the Supreme Court has consistently ruled that courts cannot issue "advisory opinions" to other branches of government.