um one thing you might check is to pull out the PS2 cord and check to see if any parts are bent or missing. By this i mean the keyboard or mouse that is not USB pull it out and see if the ends are broken, bent, et cetera. If so get a new one.
this may be a year or two late but I must say that the word centigrade is not correct the correct term is Celsius. Centigrade was done away with in the 50s. Just food for thought.