RORO01 IT IS PERFECT NOW!!!
Thank you very much for sorting out the issues I mentioned below.
I've released BatchReformat'em which batch converts images to other formats. PDF2Image and BatchReformat'em complement each other as the former converts a multiple paged PDF file to images - page by page - in various formats and the latter converts a batch of single page PDF files to images in various formats.
(Version 1.0.1)