PowerPoint Coversion Fails

In PowerPoint 2002, after I've used the "Convert to Adobe PDF" button once, the print dialog box no longer appear when I choose "Print" from File menu.
 
I can't print to PDF nor choose any other printer, PowerPoint prints the document to the default printer automatically!
 
Other versions of Office OR Acrobat 7 don't have this problem.
 
I'm using Windows XP Pro, Office XP SP3.