OK, This usually happens when your diskette has been written in a windows 98 under another file structure system (for a reference FAT, FAT32, NTFS), anyway go to the start button and then to Run click on it, in text box of the appearing dialog box write "cmd" (without quotes) then press enter or click in the OK button or Run button of the dialog box, a black screen will appear..with a cursor blinking in that screen write the next withour the quotes "a:" and then press enter, this will give you access to you floppy then write the next line "copy yourfilename.doc c:" it has to look like
a:\copy yourfilename.doc c:
see that de dot doc (.doc) next to the file name is the extension of the file for the example I used .doc cause is the MS Word file extension and it's very common. Now the command you wrote copied the file to the root of your hard drive (c:\). You can create a folder in c:\ called dfloppy and then user "copy *.* c:\dfloppy\" instead the other command. If this doesn't work you can try open the disk in another pc with a lower version of windows and try to save the files in another disk or media (CD, email, etc) and if this does not work then
probably your floppy is broken, or your diskette is damaged (in this case is you may need to write chkdsk a: in the same black screen but this could cause your files lose some info). If the disk is damage you may not recover your files from that disk.