I messed up my Windows XP when I tried to installed some applications and programs (antivirus and spyware removers). It boots fine and I can use the mouse but once I press any key from the keyboard, it freezes up. Can no longer use the mouse so I have to press the power on button. The keyboard device driver cannot be loaded and the IRQ is in conflict with the PS2 mouse. Tried to upgrade but can't. I tried to delete but the same problem persist when I warm boot again. What can I do?