If you're looking to change careers, then an MBA is a great professional degree to earn. There are several questions you'll have to answer going into an MBA, both for yourself and for the admissions committees.
1. Why an MBA and why now? I'm a career changer too, and answering that question well (i.e. have well articulated career goals) is key to making AdComs understand that you'll make a positive contribution both as a student and by furthering their brand as a professional.
2. That you have a significant contribution to make as a student. I don't know much about paralegal work, but my, likely ignorant, assumption is that you don't have actual the managerial or leadership experience since graduation. Highlighting the project and office management experience you mentioned will be important.
To answer your questions:
a. An MBA from a name brand school will definitely help you switch careers. You'll have access to your school's alumni network and recruiting infrastructure, which will help you find a place to work. Schools want you to be successful. Undergraduate schools, perhaps especially Ivies, aren't as concerned with your career placement and advancement. There, you're one of many students and the Ivy brand is already well established.
b. I can't speak too much about UW or Seattle U, but in general, admissions standards at part-time programs are more lenient than at full-time programs. As an example, per Business Week's MBA rankings, there are 217 full-time MBA students at Washington and 290 part-time students (link below). The average GMAT was 645 for the part-time program and 681 for the full-time program. In other words, there are more students, with somewhat lower standards, and a smaller potential pool of applicants (local professionals vice worldwide). Part-time programs are a cash cow for schools, because they don't need to add much to create a program while charging the same rate as a full-time program. If you can answer the leadership and career vision questions successfully (and score well on the GMAT), you should definitely be competitive.http://www.businessweek.com/bschools/ra ... ngton.html