OK - I've had a look at the files you sent me. They appear to be the default ones that are found on a windows 98/ME boot floppy disk, but it is unusual to have these as the boot files for your hard disk installed version of windows. Did these files definitely come from your c:\ directory? When you boot the PC, does it give a menu with the options 'start with CDROM support' 'start without CDROM support' and 'help'?
If the above 2 questions are TRUE, then as a troubleshooting step can you do this:
First of all, if you haven't already got one, make sure you have created a windows rescue disk (go to start menu -> settings -> control panel -> add/remove hardware -> rescue disk tab and click on 'create disk' (you'll need a spare floppy disk). This is just a precautionary step incase anything goes wrong.
Then, rename 2 files. Rename autoexec.bat to auto.bat and config.sys to conf.sys. Reboot, and see if your drives are still in compatability mode.
If for any reason you cannot reboot after renaming those 2 files, boot off the rescue disk & type these commands at the a:\> prompt (pressing enter after each one):
ren conf.sys config.sys
ren auto.bat autoexec.bat
This will rename the files back to their original names
