I'm in a similar situation, almost 33 years old and looking for a complete career change.
I thought of LE too.....Cops where I live start around $80k, with some guys earning $150k after a few years. An instructor at the academy I went to managed to earn $420k with overtime and all of his various bonuses (for having a degree, being fluent in a foreign language that is useful, being able to ride a motorcycle, etc you get a small percentage tacked on to your salary; ex. language is 5% increase).
I wanted it badly but they passed on me because of my work history (30 years old at the time of academy with only my own business as work history after college; they seemed to think it was fishy that I only did that for 10 years or that I didn't pay enough taxes or some BS).
I would never suggest it if you weren't interested in doing that type of work though. You really have to choose something that you are interested in.
I looked into fire as well.... all the firefighters I know are extremely happy with their job, pay and benefits are very good, you work very few total days per month because you are paid to sleep at firehouse, and millions of other benefits it would take pages to write. The only downside is how competitive it is. So many applicants for so few positions. Becoming a paramedic increased your chances, but is more schooling and still tough to get in.
The medical field seems to be where its at. Nursing is a great field, as others mentioned before me. I know a few people that went that route and are very happy. So little schooling compared to other med jobs with high pay. Many opportunities to advance too, an old college friend of mine is going to be a nurse anesthetist (can't believe I spelled it right on the first try!) and they make some serious loot (200k where he's at in Idaho!).
Nurse Practitioner is 2 years I think, but so is Physicians Assistant....they are very similar, and some schools are combining them now. I like the idea of PA just because the name doesn't have nursing in it.... sounds petty and immature, but I never liked the idea of being called a nurse no matter how good of a job it is.
I am actually considering joining the Air Force to do their MD program. I always was interested in becoming a doctor but couldn't afford it. I have two more years left before I am too old to join up and do their program. That is something to look into if you want to do some serious schooling but are afraid of what it might cost. The armed forces pay for it all and you owe them some years of service when it is all done.... I believe the army is ten years, AF I think is 8.
A few friends are in the union and operate heavy equipment. They all started at $45 an hour and there is tons of room to move up it seems. Crane operators can make serious money. They are all telling me to give it a shot. If you are into that type of work maybe you should check out your local union. Sometimes I wish I didn't bother with college and just took a shot at LE/Fire right away, then joined the union if neither of those worked.
Good luck with whatever you decide to do.