I had trouble with this before to.  What I do is boot normally, but don't
let Windows completely come up.  Right before the desktop and the icons are
due to come up, hit Ctrl+Alt+Delete.  Then when the next reboot takes place,
you will get a list of options to pick from; one of them being Safe Mode.

You wrote:
I am trying to boot a computer into safe mode so that I can run scandisk.
I can't get it to give me the startup menu.    I am running Windows 98 SE;
help tells me that I should hold down the ctrl key or the f8 key.   Have
done both; Windows continues to load.   I looked up information on the
motherboard thinking maybe the startup menu is motherboard specific and not
os specific.   But I'm a little out of my depth here -- it is a Super Micro
(6389) board running AMIBIOS.   (Not sure of my use of these terms....  But
those are the right names.)   Does anyone have any suggestions for getting
the startup menu to appear?

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