I have frequently "printed" a snapshot file to Acrobat Distiller as ittech73 suggests. It works fine. I have also created .pdf files directly from Access by printing to Distiller. I have never tried it, but you should be able to set Distiller up as the specific printer for your report, and then output it automatically as a .pdf from code.
Of course, you do need Distiller installed on the PC doing the conversion . . . . .