XP install hangs at Windows Setup with floppy light on - ANSWER

I'm just posting the answer to a problem that caused me to pull my hair out
for a long time until I finally found the answer deep within a thread
somewhere online. But it was too hard to find the answer, so I'm posting
it.

Symptom? During an installation of Windows XP, the install hung after the
first detecting hardware screen, and on the blue "Windows Setup" screen.
This was before any text at the bottom (such as the text that says to press
F6 to load drivers, etc.) AND, during this hang (frozen screen), the
floppy drive light was stuck on.

The answer? Unplug your card reader while installing XP! Solved the
problem immediately.

I was building a system, and I had an internal card reader, so obviously I
hooked it all up inside the case before installing Windows.

Hope this helps someone.