A lot depends on how the file is set up, but if you've used styles you could probably remove all text with any particular style using Find/Change. Select the paragraph style in the Find Format options, leave everything else blank, and change all.
If the headers and such are part of threaded stories, though, you'll really have a mess trying to put things back.
I'm not sure I completely understand. The file is simply a 200 page+ Word document that was autoplaced in InDesign. You've been really helpful to me with this In Design document - thankyou. What I'm getting at is that because I increased the gutter size to comply with printing specifications after I placed the Word document for the first time - some text that was on page 100 and was the start of a chapter - and therefore had no header, now appears on page 110 in the new file which in the original placing of the text had got a header and footer on. All I want to do is delete the story text - ie the Word document that was autoplaced.
OK, in that case I think I'd select all the pages except the first page in the Pages panel and delete them. On the first page put the text cursor in the text frame (if you didn't use some sort of master text frame), select all and delete. Now just palce the Word doc again, autoflowing to add pages.
If you did use some sort of master page text frame, delete the text frame on page one, reapply the master, and place the word file again.
I'd do this on a copy for safety.