I think you should definitely explain why you are applying to law school because that is a question that the admissions people will be asking. Perhaps try talking about the things that made you want to start your own business in the first place (ambition, independence, quest for novelty) and how those same qualities now are driving you to go to law school? I wouldn't worry about it being boring...as long as you don't just repeat what is on your resume and write well, it should be interesting.