sew your own diapers

Well, if you saw my post in the chat section, you know that I now consider my serger to be my NEMESIS.  Maybe y'all can help me feel some love for my serger by answering a few questions!

1)  It's a 2/3/4 serger (Kenmore).  Got it off Craigslist, so classes weren't an option.  Now, the two thread seam:  can I use that, or do I have to use the four thread?

2)  Which is best for sewing a hemp doubler?  2, 3, or 4 thread seam?  Do I want flatlock?

3)  How about serging the Babymoon pads and soakers?  2, 3, or 4?
This thing uses an insane amount of thread, so I'm trying to get by with using the 2 thread option.  

OK, I just saw on a website that a 2-thread application doesn't sew a seam--it just finishes it.  So, if I were to make a doubler, then I would have to sew them together with my regualr sewing machine, but I could use the serger to finish the seam?  Is that right?  And what about the cutter?  Would I disengage it if I used the 2-thread?  PLEASE HELP!!!

Ack, I'm sorry this question is so old with no answers!  If it helps at all (and you probably solved your problem already) I always use a 4 thread, I almost never do anything less for anything!