Can you boot into the main (usually hidden) Administrator account?
In XP Home that account is available only in Safe Mode.
In XP Pro, you can get the main Administrator account logon to appear at the Welcome screen by pressing Ctrl/Alt/Del twice.
Most people don't bother to password it so when asked for the Administrator password, leave the password field blank and press the Enter key.
If you can get into that main Administrator account, you can do pretty much anything...including running the downloaded file...so be careful while you're there.
