There is a possibility the issue is with the Windows XP Disc that you are using. Kindly, check in another computer if you are able to boot using the same Windows XP Disc. If the computer doesn't boot with this Disc try using a different Windows XP Disc. However, if the other computer boots with this Disc, please try running Dell 32-bit Diagnostics on the computer. Click here
to find steps on how to run Dell 32-bit Diagnostics. If the Diagnostics returns any error code(s) please reply with the same.
If the issue persists, please reply with the exact system Model Number your Dell Laptop. Is it Latitude 2500 or Inspiron 2500?
To know more about Dell's products, services and drivers & downloads, please go to http://dell.to/YBlak6