As a general statement, the legal field will provide higher than average pay and also higher than average stress and hours. It is competitive in terms of hiring, but it is not nearly as hard to just get a job as is professional flying.
The field is quite varied. Lawyers do anything from personal injury litigation ("ambulance chasing") to patents and trademarks to taxes to employment law to writing wills. The field is becoming more and more specialized and the number of "general practitioners" is going down. For example, because of the tax implications, the stakes can be so high in estate planning that wills (which might seem like a simple and basic item) are usually done by a specialist.
As a lawyer, You can practice in a corporation, a big firm, the government, or a small firm, each of which has its own pluses and minuses. Once you are licensed, it is also possible to go out and open your own firm, but it's difficult to start out that way. In law firms, you generally start out as an "associate", paid a salary. After 5 to 10 years, you may be made a "partner", which entites you to a share of the firms profits and also gives you managment responsibility.
The pay varies a lot. For example, a litigator in a big urban center who wins big lawsuits might make millons of dollars a year. A public defender or other government employee, or a legal aid attorney might only make in the $30K range. As an average, it is reasonable to expect to earn between 60,000 and 100,000 as a starting salary in a big city. Firms that pay that much will definitely expect you to produce between 1800 and 2200 "billable" hours per year. You might have to work a 60+ hour week to make that many hours than can be billed to a client.
I am a patent lawyer. I have an engineering degree plus a law degree. Most of what I do is writing patent applications and shepherding them through the U.S. Patent Office.
Key points of advice:
(1) Try not to go for a "pre-law" degree. Get something else to give you a fallback career and to broaden your experience. Like airlines, law schools don't really care what your degree is in. With the way that some degree programs are being "watered down" nowadays, a degree in a hard science or math-oriented business degree would be great for flying or the law.
(2) The most important consideration in law school is the school's reputation. This will have a major impact on your job search. Remember the old joke about "what do you call the guy who graduated last in his medical school class? Doctor!" The same it true for lawyers, but even the "C" students at Ivy league schools get better jobs than those at lower-ranked schools.
(3) Like flying professionally, you will be subjected to an extensive background check and character review in order to get a law license. This will include all of your medical records and any court records, including parking & speeding tickets and juvenille records (even those that would be considered "sealed" otherwise). So, best to keep your nose clean and watch the partying in college. I know of at least one guy who went all the way through law school and then was barred for life from taking the bar exam.
(4) Grades, grades, grades - anyone who graduates law school has a basic level of knowledge. What you want to do is to have a high class ranking so you get on the list of those who get on-campus job interviews from big, prestigous, high-paying firms.
OK, sorry for the rambling. Want to know anything else, email me.