Using the Export command in InDesign yields large, complex and unreliable PDF files. A better way is to simple print a PostScript File and use Acrobat Distiller to make the PDF file.
Chose Print from the file menu and make your dialog box match the above sample. Hit the Save button and send the PDF file to a convenient location. Open Acrobat Distiller, making sure your settings are correct, then Open the postscript file you just created. Distiller would convert the file to a PDF.