See if any of these things will help you further:
Go into the BIOS by hitting the Del key during bootup. Click down to PnP/PCI and hit enter. Then check if the "Resources controlled by" is set to Auto. If not, set it to Auto. Then "Esc" back to the previous menu and select "User Password". See if it is set or disabled or requires an entry.
Are you using a ps/2 mouse/keyboard or usb? Does the alternative work?
If the above doesn't help, you may wish to replace or refresh the CMOS battery. This step can involve losing all your settings, so you may wish to read more about this step before taking it. For laptops this is not as straightforward as for towers and desktops. Please see these two articles: http://murfsgarage.cybertechhelp.com/cmos.htmhttp://www.computerhope.com/issues/ch000976.htm