Regarding doing all your education up-front or working for a bit between degrees:
Personally, I found it a lot easier to go back to school after working for a few years. I think it's easy to get burned out on school, so taking a break between a bachelor's and a master's was a good idea. Working for a few years also lets you focus on where you want to take your education, which might change dramatically from what you thought after spending a few years working and gaining "on-the-ground" experience in your field.