The hardware is dead.
There is a keyboard logger (trojan) installed.
There is an incomplete install of the Windows OS. (motherboard drivers, Windows Update, etc.)
Your post is too light on details so I'm tossing out a few ideas to get the ball rolling.
In closing, I've seen this happen and Windows not be the cause (it was a hardware issue)
On my other computer no keyboards work propley when you plug them in because when u go to press a charactor u have to hold it down for about 5 seconds before it shows up. The same thing happens to wateva keyboard you plug in so its defentley a proplem on windows.
Its windows Xp by the way umm if anyone could please help because i really need this computer working.