Crux,
I believe you may have PC-Doctor confused with another program. PC-Doctor is a hardware diagnostics program that does not do anything unless it is run. We don't check anything on startup, run things in the background or pop up any windows.
PC-Doctor is installed by many OEMs to assist support staff in diagnosing hardware related issues. The behavior you describe is not part of the PC-Doctor method of operation. There are other “Doctor” programs that would do this. Are you sure the window says PC-Doctor not bug doctor or something else?
-Fred