Brendhan-let's try this run the Registry Checker that comes with Windows 98.
Press start button,go to Run and type"scanregw.exe"without the quotes.
ScanReg maintains,by default 5 separate backups of your registry files,as
well as some other important system files, including win.ini and
system.ini.It compresses the backups into 5 separate.cab files, named
rb000.cab,rb001.cab etc.
You'll have to check the file dates for the most recent backup(view the
files in Explorer's Details view,or type DIR in DOS,as the numbers won't be
a reliable indicator of their age.The .cab backup files are in the hidden
C:\Windows\sysbckup folder;you'll see this folder if you've got Windows to
display hidden files.
Any way,you know that the last .cab file isn't any good because your machine
doesn't boot,choose another .cab file just drag it out of the Cabinet window
that appears when you double click the .cab file and drop it in your Windows
folder.Do this for each of the registry files System.dat and User.dat;if
you're asked click Yes to confirm that you are replacing the file that's
there.

There is more to this,as far as changing the default of 5 backups,but that
is another matter,see if this does anything.
Maybe you've turned your machine on more than 5 times since the problem
started and none of your files are good.---daryl
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