This is an interesting question to consider. Personally, I don't think I would have handled it in the same way that Orlando did. His open challenge of his brother and then the way that he deliberately humiliates Oliver by showing his physical superiority over his brother by wrestling him only serves to antagonise Oliver and to make his hatred of Orlando more profound. It was not a very wise mood, however happy it would have made Orlando feel to finally express his frustrations and anger at his brother. However, we need to remember that Orlando is presented as an honest and simple character, so these actions suit who he is.
I personally would have tried to adopt a softly, softly approach, staying quiet and appearing to be content with my lot whilst at the same time working to gain support for my position with other nobles, perhaps friends of my deceased father, in court, and even appealing to the Duke. If it was decreed in the will that Oliver should look to his brother, that would give his case weight in front of the court.