I don't know. But from the text file that came with the software "2. The standard DIR and DEL commands will NOT work 100%"
A&b are usually reserved for floppies, but if that what you saw then a:\ it is. If a:\ wasn't a valid or not ready drive you would have recieved a message stating so.
Since you are in the a: drive, we'll do the following
xcopy(space)a:\ntoskernl.exe(space)c:\windows\system32(enter)
You may get a message like do you want to over write existing file.If so type y and hit enter.
If there where instructions for exiting use them. If not remove the cd, give the computer the three finger salute(control,alt,del at the same time). Cross said fingers,say a prayer hopefully your computer will boot.
Post back with the results. It's late here and I've got an early morning. We can carry on tomorrow.