How to back out of Win XP Pro installation

[A Confused user]

I have a pc fully loaded with various applications.
Due to some softwares uninstallations, files deletions ... The machine is
messed up.
It keeps looking for some files and then reboots.

I try to re-install (NOT do a fresh install because the machine is loaded
with applications) Win XP Pro.

When it gets to the key-in the s/n of Win XP, the keyboard would not work at
all.
I try several other keyboards (usb & ps/2), same results, Keyboard would not
work.

How do I back out of the re-installation of Win XP ???
The machine is basically stuck because something makes the keyboard not
working. The keyboard works FINE prior to entering Win graphical mode!!!

I need HELP ! I appreciate any kind of suggestions that you might have

 

[Andrew E.]

Youre keyboard will work in DOS with the PS/2 plugged in,the usb can remain
plugged as well if you have both plugs.Also,youre BIOS settings will enable
or disable usb keyboard,the settings "On chip PCI devices" allows for usb to
run in DOS or the OS..Also,to start fresh,unplug power to pc,remove the
battery
for 5 minutes or so,replace battery,start pc.You'll need to reset BIOS
settings
date/time,etc as all go back to its default settings as it left the mfg,set
time/date,
load optimal default settings (end of BIOS),then go thru & adjust for any
add-in
devices,set BIOS to boot to xp cd,hd 2nd priority,install xp cd,boot to
cd,reinstall
xp.Thier really is no "back-out" option..