I'm familiar with CNA and medical assistant so here goes
1. CNAS you do a lot of basic stuff like taking vitals ect. Medical Assistant you will work throughout an office doing everything from phones to injections ect.
2. CNA is the most useful I think. Most RN programs require CNA and some even require its next step CNA2. Medical Assisting is a whole other field and a separate degree. Most likely you couldn't use most of your prereqs for Medical Assisting.
3. It depends on where you live, CNAs in some areas can walk out of school into a job in others they spend months looking. Some hospitals use PCTs some not at all. Medical Assisting in my area is huge right now but again in others they can't find a job.
4. CNA or PCT based on the limited knowledge I have of them from this board.
5. Honestly I wouldn't do any of these online. I've seen a few programs advertised cna online or pct online the like but I know with CNA the states are strict as to what training they accept to take the state test, Medical Assisting is a 2 year degree that I have yet to see online. There is no substitute for classroom and clinical exp, in my op.
I've been in exactly your shoes I know its tough with kids. CNA is a fairly quick program but unless your lucky enough to land a hospital job the work can be gross and low paying. Medical Assisting is a fairly easy program to get acceptance to but be mindful of the area you live in. I've gone back and forth as to enrolling and for awhile I was sure I didn't want to do it, then I met some medical professionals who have ditched almost all their other staff for medical assistants and are eager to hire more. And I put in a short stint as a CNA, I do not in any way want to do that for two plus years while I finish my prereqs and then the possible 2 plus year waiting list (from the school itself). I was lucky I got into the best medical assisting program (best reputation best grad to hire ratio) around. RN is the best choice by all means and LPN an equally intensive program would be my second choice if I didn't want to wait the years. But as is I can get my medical Assisting degree in two years go back and with a great gpa get into Respiratory therapy or Medical Lab Tech and come out with two degrees in the time it would take me to get into RN.