I need often put information from a table in e-mail(plain format). This can
be done using mono-spaced fonts and space characters.

Probably, it possible use Microsoft Word and the special converter "Text
With Layout", this converter will convert Word tables to this format.

MS Word have two options in "Save as type": save as "MS-DOS Text with
Layout" and "Text with Layout". What is difference and which option need be
used?

Thank you.