Usenet will eventually be like telnet and gopher. Some ISP's have stopped offering usenet because their subs didn't know what it was and weren't using it. What a shame
There are utilities that will allow R/W access of NTFS volumes from DOS but running Win9x on an NTFS volume can't be done. Perhaps you're thinking of a program like VMware which would allow you to run almost any OS using emulation.
To start profile manager go to Start->Run and enter firefox.exe -profilemanager
Make sure Firefox is not running before using profile manager. Check using Task Manager.
There are two reasons for this message.
(1)The installation file was corrupted during the download.
(2)The installation file is not complete.
Did you use a download manager?
Run chkdsk on the drive. Right-click on the drive and select Properties and then the Tools tab. Under Error Checking click the Check Now button and then check both options. Cross you fingers.