File > Export > Adobe PDF (Print).
To expand on Bob and Steve's responses, the fact is that “printing” PostScript from InDesign yields PostScript optimized for printing to a live printer and not for production of PDF! Adobe strongly recommends PDF export as opposed to PDF produced by distillation of PostScript!!!!!
PDF produced by distillation of PostScript loses color management, live transparency, any and all hyperlinks. The resultant PDF may be readily searchable (for text) and may have problems in terms of fonts, especially if you try to subsequently merge such PDF files or perform any Acrobat-based touch up operations.