• Masters in Social Work (MSW)
• Masters in Marriage and Family Therapy (MFT)
• Masters in School Psychology
• Masters in Counseling Psychology
• Doctorate in Counseling Psychology
• Doctorate in Clinical Psychology (PsyD or PhD)
• Medical Doctorate in Psychiatry (requires pre-med classes)
• There are alot of unique Master's degrees available. I've heard of degrees like a Masters in Applied Behavior Analysis, a Masters in Learning Disabilities Counseling, etc.

The variability in both clinical and counseling programs is so tremendous that there is almost no good answer to this question. Clinical psychology programs may be slightly more competitive, but this is changing and of course depends greatly on which programs you're talking about. Some counseling psych programs are more oriented to training academic counselors for college/university counseling centers. Some clinical psychology programs might be more focused on training psychotherapists than academic counselors. But one strong claim that can be safely made is that almost all clinical psychology PhD programs emphasize research more than clinical skills. This is also true of many counseling psychology PhD programs. The clinical PsyD degree, on the other hand, is focused almost exclusively on psychotherapy training. It makes little sense to apply only to clinical programs or only counseling programs; applicants should carefully study programs of both kinds and identify those that best fit their interests. Applicants with little interest in research would be well-advised to pursue a high-quality PsyD degree instead of a PhD.

What makes the distinction between clinical and counseling degrees really confusing is that there are plenty of counseling psychologists who decided not to work in academic settings, and so are employed alongside clinical psychologists in hospitals, mental health agencies and private practice. Of course, there are also a few clinical psychologists who work in university counseling centers; so as you can see, the distinction is blurry. One reliable difference, however, is that clinical psychology students are almost never trained in academic counseling.

1. Research. The PsyD is less research-oriented than the PhD. Some PsyD programs do not require a dissertation, for example. If you are interested strictly in being a practicing psychologist and have no interest in teaching and research, you should seriously seek PsyD. Most PhD programs will consider you very unfavorably if you apply with the intention of being a clinical practitioner only. PhD programs invest alot in their students to train them as competent practitioners and researchers, so they expect you to be interested in research.
2. Length of time to completion of degree. With the added burden of completing important research, the PhD may take at least 5 or 6 years. The PsyD is usually shorter, although both must complete an APA-approved internship in the last year.
3. Financial Aid. The downside to not having to do research in a PsyD program is that you probably won't have the opportunity to be a research assistant, and thus, receive financial support (PhD students, on the other hand, often receive a tuition waver and a living stipend in exchange for research assisting). PsyD students often have to take out large loans that will take many years to pay back. However, since the PsyD takes less time to complete, you'll be earning money while your PhD counterparts are still finishing up their dissertations.
4. Selectivity. As you might have guessed, PsyD programs are often less selective than PhD programs because, after all, you're paying your own way.
5. One thing to watch out for with the PsyD: There are a whole lot of "Professional Schools of Psychology" popping up these days, so you have to be careful where you apply. It is always risky to apply to a clinical program (be it PsyD or PhD) that is not "APA-approved" (approved by the American Psychological Association). State licensure as a psychologist can be either very difficult or impossible if you don't attend an APA-approved program.

There is almost no difference at all in the content of what you study. However, business schools tend to have more financial resources than psychology departments, and they also tend to pay their graduate assistants more. If you are interested in organizational psychology, it would be a good idea for you to read this web page about organizational behavior PhD programs.

It's been done before--by many, in fact. It's certainly difficult, but most single parents are well-acquainted with difficulty, I think. The effect it might have on your family is something you'll have to weigh out and decide for yourself.

Masters programs should take 2 years. Doctoral programs may take from 4 to 6, but 5 years is a good heuristic (that includes the Masters, so 5 years total). There are always a few students who take a long time to finish their dissertations, but these students are sometimes viewed unfavorably both by their departments and their potential employers unless they have legitimate excuses.

This can really vary. Masters students generally don't receive any aid because they're done quickly enough to find work and pay off their loans. Most of the financial aid packages I was offered in the PhD programs I was accepted into included tuition wavers for 4 out of the 5 years and enough money to pay for rent and groceries for a single student. Living stipends vary dramatically because cost of living varies so much. A tuition waver + a $12,000/yr stipend may sound like a lot until you remember that you'll be living in Los Angeles, for example. Also, if you're at a private school and get stuck paying your own tuition any particular year, that's easily $20,000+. Choose carefully.

In general, almost any kind of graduate school can be worth it as long as you don't amass huge amounts of debt along the way. Study after study shows that, on average, people who go to graduate school make slightly more money over the course of their lives than those who do not. If you're curious about how much money you'll be making if you go into the field, check out the results of this APA salary survey.