Of course that can be done, at least on a client, assuming all the relevant software is present and properly configured.
First you think through the steps that are needed, and perform the steps manually while you write it down:
1) Open Notes document
2) Check if there is an attachment and if the filename is .doc or .docx
3) Detach the Word document to a temporary folder in the file system
4) Use a commandline tool like PDFCreator (http://www.pdfforge.org/content/create-pdf
) to create a PDF of the Word document
Now you just write the Lotusscript code to do the same.
Piece of cake.