Windows don’t pop up

I have no history to the problem. I don’t know what the user may have installed to his machine. I can’t view the event view logs. I can open the event viewer but the log windows don’t pop up. Nothing shows in the task manager but if I try to close the event viewer I get an error to close the log windows. This is just one example. I cannot open any other windows but the initial one. He has Windows 2000 Sp2. I have tried to repair the OS but no joy. (This is my Dad’s pc and he is computer illiterate. He doesn’t know what he has done). Thanks for your help