Expert converter help needed for converting to kindle keyboard

[Silveron]

I have a lot of older books (various formats) I am trying convert to kindle keyboard. I have have been converting them to doc or html to fix them (spelling errors, missing spaces between words, ect ect.) Then run them thru calibre to make a TOC and change them to mobi format for my kindle.

I am useing Kindle keyboards defalt setting 3rd font size, regular typeface. When I convert the font on the books is too small and if I up the kindles settings to the 4th font size its too big.

I am trying for continuity between all the books. Since I am convert them all to doc or html its not a problem to change the font used or the font size as well as the 'look and feel' settings in calibre. Its only books I convert that I have font size issues with, all the ones I have downloaded from amazon are all the same and pefect size. I do not want to have to change my settings everyother book.

Is there a defalt font type and size for kindle? Is there a way to check what the font type and size setting of a book? That way I find out what one of the books that are fine setting are and use them??

I have been working on the same two books for a month now useing different converters and such. Now I finally got the content fixed and a working TOC, I just feel like pulling my hair out now that I ran into font type/size issue.

Thanks in advance for any helpful info.