Taking your question
"difference between print as pdf and save as pdf"
to Google.......this was the most common reply.
There are two ways to convert a document to the PDF format: 'Save As' to save a version of the original document to a different format. ... 'Print' which intercepts the printer output from a program to make a PDF file. Instead of a paper page coming out – a PDF file is created which looks like the paper pages.If you're pc is failing on Print to PDF, my guess is there may be something not right in a setting somewhere.
Try this......
https://cutepdf-writer.en.softonic.com/Get the download for CutePDF from Softonic (open source) and install it. It will be a new selection in your printer options (CutePDF) when you want to print something. We been using this CutePDF for more years than I can remember. It does a nice job to output a print file to a .pdf format file. Maybe that will work for you.