I think you can install XP on that computer. However it won't run that grand. You could reinstall the current OS that is on it. That would delete all the login issues you are having.
If the BIOS says the login password is not assigned, then the computer does not have a BIOS password assigned. The login password is done by the OS, not the BIOS.
To clear a login password, you'll need to know which OS is installed. Is it ME or 2000?
http://www.petri.co.il/forgot_admini...ogon_trick.htm
check that page for getting past the admin login on windows 2000.. but it is a very involved process. You'd be better off just reformatting and starting fresh.
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