user name it says demo
Was that your user name?
Have you tried just hitting Enter at that point?
When you first start your computer, before Windows ever does anything, do you see a screen from "Creative" or "Intel" or "AMD"?
If so are there no instructions at the bottom of the screen?
Just as a test re start your computer and constantly tap tap tap the Delete key. See what happens.
What was the original OS? XP SP1 or just XP? Home or Pro?
You can create the 6 floppy boot disks from here depending on your original version:
http://support.microsoft.com/kb/310994
If we go this far, meaning none of the above work, we can try working through the Recovery Console but of course the keyboard must work.
http://support.microsoft.com/kb/314058
The best way to deal with the keyboard is via the BIOS so try the Delete thingy.