Nursing is a troubled industry these days. There absolutely, positively IS NO "shortage" right now and the job outlook, especially for new grads, is bleak and will be for a while. Sorry to burst any bubbles, but nursing is in no way what it used to be. Your perspective is noble, but not realistic. Peruse this forum carefully, talk with nurses and maybe shadow a few if you can. You'll see quickly - it's not the cheerful, active, helping profession it once was.
Your experience and age would both help and hinder you; bringing on a 45 year old former lawyer with no nursing experience is a gamble for any employer. A lot of nurses in that age range are almost expected to have or be pursuing a Masters degree. And right now the market is clogged with new grads, a good portion of them 40-something "2nd careerists." When the recession hit, scores of people ran to nursing, believing it to be a "recession proof" vocation that was about helping people. Again, read this forum carefully and you'll see many posts from those very people who are now unemployed, in debt and cannot find work.
Nursing's career track today looks roughly like this:
Languish on a college waiting list to be accepted, 1-2 years;
Toil away for 2-4 years in a brutal, competitive nursing program
Begin job hunt;
After several months to a year maybe find a nursing home/HH agency that will hire new grads;
Put your time in the trenches passing meds, dealing with psychotic families and 40:1 ratios, and Medicare fraud, 1-2 years;
Maybe land a hospital job with a decent Magnet joint that hires BSNs;
Work a med surg floor 12 hour nights to start;
Be forced into OT because of the documentation demands, be chewed up and spit out by more experienced nurses and snotty managers, your back and feet get destroyed from the physical expectations, and be worked to death by management who have profit in mind over people, be treated like a glorified waitress, multiple UTIs from holding pee for hours, 2-4 years;
Make another career change, or go for a Masters to get into management or teaching
By then, you'll be what age?
Compound this with your aging parent situation.
Still appeal to you?
Again I'm sorry to be so blunt. I'm not cynical, I'm a realist. I went to BSN school at the age of 32 after 10 years in IT. Graduated in 2007 and have had very good luck because I managed to sneak in under the door pre-recession. I've keenly observed how drastically the profession has changed in just 6 years. I think at some point the baby boomers will finally retire like we thought they would pre-recession, but the turnaround will be slow. Obamacare will also place more emphasis on preventative care - and I anticipate nursing education to scramble to adapt their model to prepare students for that.
If you still want to go for it, at your age with your law experience, I'd go for an MSN with a strong concentration on Public and Community health nursing & case management. It'll be nurses with that training who will be sorely needed once O-care kicks the dollars down to fund community clinics and preventative health education.
Hope this helps. Good luck to you.