I've been using Ka-Blam for years now...when they ask for Publishing name, they mean "what is the publishing imprint that you are publishing your books under"? My publishing name/imprint is Studio Brie Comix...
For black & white/grayscale you just need a file dpi of 300(or slightly higher; I just use 300 and PDF format)- any less and the quality loss will show. Make sure your pages are formatted CORRECTLY and to the file type that they require(they have templates that you can use to size/fit your pages)...the paper they print the comics on is better than your average "copy machine" quality; the cover stock is the same.