I receive some e-mails in French and Spanish which I do not read that
well. Sometimes I re-write the text in an automatic translation box
like  www.google.com/language or www.freetranslations.com or similar
to get a version in English.

Is it possible somehow to translate directly on the e-mails - without
re-writing them ? 

Can out-going e-mails be translated, i.e. "click" them into French or
Spanish before they go out?  Ideal if one can check the outgoing text
before pressing SEND.  And very best solution would be if the
out-going e-mail could contain both the original text in English and
below the automatic translation.

If any of all this is possible what are then the step-by-step procedures ?

I know of the altavista.com toolbar but that is for webpages , I heard
of one service that does email

http://www.t-mail.com/

But bare in mind on the fly translation is spotty at the best , since
you have used translation webpages before you know they will give you
quite comic results at times , and i doubt that that is something you
would wish to send out

http://www.mail2world.com/s/m2wpublic/services/part1.asp this should do it.