We spilled a little water into our Toshiba laptob, and it has affected the keyboard. At first, only 6 or 7 keys worked, but now the computer beeps constantly as if a key is 'stuck'. If I can disable the keyboard so a USB keyboard can be used, we can use the laptop as is until it can be repaired. How can I do this?

In control panel go to system, select the hardware tab and click on the Device Manager button

In the list, expand keyboards, right click the laptops keyboard and select Disable
(you might want to unplug the USB one so you don't get confused which ones which)

Although that would probably work if I could get to that screen. But I can't even get it to boot up.