I would certainly recommend working a few years before going back to school. I amazed at the subtle differences between the "experienced" applicants and the "no experience" applicants. The "no experience" crowd does not really get the payback either. MBA school is the grind and do no go unless you really want to devote a couple of years to education. Graduate school is not fun.
I am doing the full-time program and here is how I would look at the PT/FT option. If you have a great job with a great company, go part-time. By doing the PT, you should be happy with what is in front of you and just want the advanced degree to move you up the ladder. If you want to totally change careers or if you are unhappy with where you are in your career, go full-time. However, I do believe the students that go full-time have a better chance of finishing the degree than the part-time students. I have seen people get married, have kids, etc. and the degree doesn't mean as much to them anymore.