General ⇒ first time Latxer trying to convert a docx file

[MarkTierno]

I have a paper I've written that I've discovered must be in LatX format in order to submit to a journal. Never submitted to a journal before but the paper is important. Anyway, I wrote it in docx and dumped it into a pdf. I've tried various online converters, to varying degrees of success (or lack thereof); anything from 168K to 12MB in output; trying to convert from both docx and pdf. Even for one "latex" output that looked reasonable I still had no means to view it to verify. So I installed MacTex; 4GB later I can't get it to view the converted file in question, or load up my docx or pdf originals.
The file is about 55 pages, and has about a dozen pictures in it in PNG format, and uses fonts commonly available via MS Word (with a few greek symbols in my equations); no fancy integral or other symbols, just a few greek symbols pulled from normal fonts. Help! I don't know where to go or what to try next, I just know that I'm at the stage where I don't know what it is that I don't know.