For anyone having problems with saving a PDF file from within SW2004
Saving a file as PDF from within SolidWorks stopped working after I uninstalled SW 2004 and then reinstalled using SW instructions (i.e. delete SW registry folders). I did take it one step further (probably the cause of my problems) and removed the Bluebeam folders from the Windows XP registry. Anyways, what I recently discovered is that adding a new printer by means of Windows Printers/Faxes also allows SaveAs PDF from within SolidWorks. In my case I downloaded and installed CuteWriter PDF (free) and GhostScript 8.50 also free to the public and then setup a postscript printer (Bluebeam still checked in SW addins).
And there is always the alternate method of saving a file to PDF by choosing Print, then choosing CuteWriter PDF as the printer.