I don't have any personal experience with completing a minor but I had a few friends during my undergrad that completed (or tried to complete a minor). Just in case you're not aware, there are a few things you should note about minors:
- Your minor will NOT show up on your degree when you graduate. (it only shows on your transcript and it is your responsibility to tell graduate schools and employers that you have it). Also, you need to declare to the registrars office prior to graduating that you have completed the required courses for the minor in order for it to appear on your final transcript.
- Start planning what courses you need to take to complete your minor now as you aren't guaranteed to get into those courses and a lot are limited to people in that program.
- Minors will most likely use up most of your elective courses during your four years, especially if it's outside of the commerce department. Keep this in mind as the courses needed to complete your minor in the later years may be just as difficult (or more difficult) than your major 3rd/4th year courses.
As far as choosing your specific minor, I would recommend talking to upper year students and hearing what they recommend since they know what your course load will be like in later years and what minors may look better to employers. Also speak with you academic advisor to see what they think as I'm sure they've had hundreds of students complete minors and my have some helpful tips for you. It may also help to speak with your professors, especially ones that have worked in fields that you're interested in, to see what kind of minor might benefit you the most.
Sorry for the long post. Best of luck!