[slayda]

First, do your books have DRM (Digital Rights Management), i.e. are encrypted. If they are then Calibre will not handle them. If not, Calibre should handle the PDF files and you can use MS Word (or Open office - free download) to convert the DOC to RTF filesand Calibre will handle them.

If they do have DRM (and I don't think the DOC files could but am not sure) then you'll have to deal with the DRM first.

Once Calibre will handle the files, you'll need to convert them to PRC for the Kindle to read them. However, my results with Calibre converting to PRC and trying to read on the Kindle were unsatisfactory - the font was too small and would not change sizes on the Kindle. I haven't tried with the latest version of Calibre yet. I prefer Mobipocket Creator but I don't think it will do batch jobs, i.e. you'd have to do them one at a time.