Hi - 

I would like to be able to have visitors to our website click a link
which would open a PDF document AND then automatically trigger the
Adobe Acrobat print dialogue box. (In case it helps you can trigger
this once the document is open in Acrobat with "control+p")

There is a way to do this with web pages through javascript but I
haven't been able to find any documentation on how to do it with a
PDF.

Similarly I would like to trigger the email option too.  (In Adobe
Acrobat - file|email). So in other words, visitors click a link to
attach the PDF document for emailing.

Thank you very much!

To get the require functionality you will have to embed javascript
within the PDF file. You will need to take a look at the Adobe Acrobat
Javascript Reference available at
http://partners.adobe.com/public/developer/en/acrobat/sdk/AcroJS.pdf

and the Acrobat Javascriptitng guide available at
http://partners.adobe.com/public/developer/en/acrobat/sdk/AcroJSGuide.pdf

For eg, to provide the Print dialog automatically after the PDF file
is opened (so that the user can print pages 1-10), you will have to
include the following javascript in the pdf file :-

this.print({
bUI: true,
bSilent: true,
bShrinkToFit: true,
nStart: 1,
nEnd: 10
});

To see more about printing and mailing documents, please have a look
at pages 284 and 289 of Acrobat Javascript Scripting Reference [ not
the Scripting Guide].
You should find everything there hopefully. And do have a look at the
restrictions placed on these by the Acrobat 7.0 model. Certain
automated actions may not be possible [which were earlier posssible in
v6.0 and earlier].
Regards,
Vineet Reynolds