Off-topic: Backing up non-DOS files in Windows 98

[BrennerNY@xxxxxxxx]

       My computer has been diagnosed by the local computer repair professional -- hitherto reliable -- as having a corrupt file in its Windows 98 operating system. It's acting in a highly irrational manner. He advises reinstalling the operating system from the original disks, obviously first copying everything I want to keep onto disks. 
       I have no problem backing up all my Xywrite files on Zip disks. But I'm having a problem with all my non-DOS files -- all those Word and PDF documents. I have a Zip drive (Drive E) , but Windows 98 only offers me the option of copying to a disk in Drive A -- i.e., to small floppies. 
       The answer would appear to do these transfers in DOS. But I can't figure out the correct DOS directory name for "My Documents", for example. Can anyone on the list tell me how to identify non-DOS files at the DOS prompt, so I can copy them onto a Zip disk in Drive E?
       Lynn Brenner
       BrennerNY@xxxxxxxx