Bill,
What do you mean by "step through" the start up? Are you trying to make it quicker somehow? Does the link below help you get that done? (You can skip the description of "resources" at the top because it refers to older versions of Windows, but begin with the part about "msconfig".)
How To Shut Down Unnecessary Start Up Programs
Hope this helps and let us know more..
Grif
Is there a way that I can step through the start-up on Windows XP Home Edition?

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