No Administrator password on XP PC.

Hello,
I purchased a 2nd hand Pentium 4 PC running Windows XP. I do not have the Administrator's password. There are no ther users. I have tried to create a boot CD on another PC, but I don't think i'm using it correctly on the locked PC. When I select IDE CD-ROM Device, it F1 to retry or F2 for setup. Some suggestions to fix the problem of no password involve entering commands in the CMD prompt. I cannot get this to come up. The PC just displays many lines of 'multidisk, rdisk, partition msgs, then the PC continues start up to logon screen. Any or all suggestions welcomed, except to give up. Thanks in anticipation. David.