Forgot my Windows 7 Password, but can still login with my finger

You can set the password through the command prompt without knowing the previous password. Here's how:

1. Open an administrative command prompt (Right-click Command Prompt and Run as Administrator).
2. Type set username in the command prompt. You will see your username (useful if you don't know what it is from the OEM, etc.)
3. Type net user username * (replace username with the username from step 2.
4. Type in your new password and press enter. You won't see any stars or anything as you're typing - but it is typing! If you mess up you can press ctrl + c to cancel or press Backspace enough times to delete what you've typed. If you cancel, just type in the command from step 3 again.
5. Type in the same password again and press enter.

If it worked you should see The command completed successfully.

Check this link, you can do this using the NET USER command at a command prompt. You will probably need to open your command prompt with Run As Administrator enabled.