Nikki said:
This is what I have done in the past but the version of Publisher I
have now (2000) does not show "Save as Picture".
Ah.
This feature is only available in Publisher 2002 and later, and is only
useful in Publisher 2003 and later.
You could copy the elements, paste them into a new publication, print a PDF
file, and convert the PDF file to a high-resolution image. (John's method
will work, but will not give a terribly good resolution)