Help a High schooler out Please

I'm a hs junior who was recently told by a school career test I'm a good match for a career in IB or PE. I know next to nothing about it, but the job descriptions sound really interesting (and so does the salary). I'm planning on going to USC for business anyway and I would really like to explore this option. I've got a couple family members in the finance/economics trade from USC but I'm not even sure what to ask so I'm coming here to get a general idea then refine my questions. I understand what the difference between the two are but which one has a better outlook for the future? Also, I see people talking about target schools and NYvsLA and I feel lost in all the lingo. What's the difference between working in those areas...where are the bigger companies and the nicer salaries? Am I more likely to get a better job with an MBA or can I get in with just an undergrad major in business from a pretty good school? What is the average starting salary really and do promotions/raises come often? And finally, do the hours stay the same from entry level to a higher position? I don't mind the crazy hours when I'm young but in my thirties/forties I don't want to feel like a part-time parent or wife. I want to be involved in my family and financially stable at the same time (if it isn't too much to ask). I know this is a lot of questions but I just thought I'd get them all out here rather than fall into the mind-numbing loop of quora and yahoo answers. Thanks in advance for your answers, they're much appreciated!