Reading binary Word documents would involve creating a parser according to the published file format specifications for the DOC format. I think this is no real feasible solution.
You could use the
Microsoft Office XML formats for reading and writing Word files - this is compatible with the 2003 and 2007 version of Word. For reading you have to ensure that the Word documents are saved in the correct format (it's called Word 2003 XML-Document in Word 2007). For writing you just have to follow the openly available XML schema. I've never used this format for writing out Office documents from PHP, but I'm using it for reading in an Excel worksheet (naturally saved as XML-Spreadsheet 2003) and displaying its data on a web page. As the files are plainly XML data it's no problem to navigate within and figure out how to extract the data you need.
The other option - a Word 2007 only option (if the OpenXML file formats are not installed in your Word 2003) - would be to ressort to
OpenXML. As databyss pointed out here the DOCX file format is just a ZIP archive with XML files included. There are a lot of resources on MSDN regarding the OpenXML file format, so you should be able to figure out how to read the data you want. Writing will be much more complicated I think - it just depends on how much time you'll invest.
Perhaps you can have a look at PHPExcel which is a library able to write to Excel 2007 files and read from Excel 2007 files using the OpenXML standard. You could get an idea of the work involved when trying to read and write OpenXML Word documents.
