ePub Conversion for eBook from Word doc

I am trying to convert my book into an .ePub file so that I can upload it in [login to view URL] for its eBook version. I need someone to help me to convert the book which is in the normal word document (& cover in PDF) to this .ePub file format. Need someone who has experience in Conversion program like (Adobe InDesign, eCub, Calibre, Google ePub Toolkit). The objective is to have all ebook readers to be able to read my ebook versions. For example iPod, Sony, Kindle etc. I understand there are freeware applications that can be used to drag and drop the document to convert into an .ePub in seconds but not sure if that allows all types of book readers to render the texts in the right font size etc. Someone with experience and knowledge of converting should be able to advice and do the job. This book does not have any graphics or Images just word test (except the Cover design). The converted file should be uploadable in [login to view URL] or similar self -publishing website.