I'm not sure what the different settings mean either, I was just happy that I got MameWah to work. I'm not even sure if it will work for you. If it doesn't, just try out the different combinations for the Send ROM Path, Extensions, and Long File Names.
T T T
T T F
T F T
T F F
F T T
F T F
F F T
F F F
That's all I did, until I finally got it to work. Good luck.