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What could be a better source for answering this question than MBA.com http://www.mba.com/why-b-school.aspx
They have an article about it though it won't answer all of your questions.
Ultimately, it boils down to something very simple: you get an MBA to propel your career forward past the barriers and hurdles you have encountered right now. The reason people get an MBA is because they don't like their current job/industry, don't see an easy way of finding the right job for them and feel that an MBA will help them build a bridge to the new role.
It does not matter who you are or what you did (gold instructor, athlete, etc) - you can get into the business school and the more unusual background, actually, the better since Schools are very concerned and focused on the diversity aspect in the class.
The only thing to choose is full time, part time, or executive mba.
You are at the age that you can go for any of those 3 with most programs being a bit skeptical about applicants over 33 (though there are plenty of those still, just requires a bit more explaining in the essays)
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