Autofit not working after save
If a text box has been set to auto-fit, and you save the document, and re-open it and the auto-fit has been lost, this has been confirmed as a bug in Powerpoint 2002/2003.
One solution is to make sure there is only one slide master.
Another is to move the text into a separate text box, unrelated to the slide master.
Printing slides to PDF
File > Print to PDF as Slides enable Scale to fit paper in Printer Properties: Advanced > Paper Size : Custom = 210 x 280 DPI cannot be 4000dpi or 3600dpi (page will be squished up). Can be 1200dpi.