Q: I locked myself out of my computer and my sister has a windows reset disk for her computer, Can I use her reset disk to unlock the password on my computer?

A: No, but you can burn a bootable Windows password reset disk with third-party software. Windows 7 lets you to create a Windows 7 password reset disk in advance in case that you forget the login password to your computer in future, and so does Windows XP/Vista. However, this created Windows password reset disk can be only used to reset Windows password for the target computer. You cannot use it to reset the password for another computer. Even so, don’t feel frustrated if you come across a similar problem as you can create a bootable Windows password reset disk through additional software.

Windows Password Unlocker is professionally designed to help individuals and companies bypass their forgotten or lost Windows login passwords. With this utility, you can create a bootable Windows password reset disk with USB drive or DVD/DVD in seconds. After that, you use the bootable Windows password reset disk to reset local administrator, domain administrator and other user passwords on all popular Windows OS, including Windows 7/Vista/XP and Windows server 2008(R2)/2003(R2)/2000. Windows Password Unlocker comes with 3 editions. So please learn the difference among each edition and make sure you get the right edition before purchase. You can take the most suitable editon to solve your Windows 7 password recovery issues or on other Windows OS, like Windows Vista/XP/2000/2003/2008 etc.

Once more tip: If your computer runs on Windows XP, there’s another free way to get back into it when it’s locked. That’s to use the built-in administrator account on it. When the logon screen appears, press Ctrl+Alt+DEL twice to bring up the classic logon box. Then try to log into that administrator account without password.

Yes, you are correct, the tool you mentioned -- Windows Password Unlocker is really nice and helpful.
I have used this tool to reset windows 7 password with ease without losing any data. Thanks.