Thanks a lot dvdbane and willy2 .
I removed those all tasks that 'program compatibility assistant' ran except 'Vice city 2.exe' one because that is one program (game) I still have installed on PC.
One of those , which is 'Yahvcfx[1].exe' is I think that malware which I accidently downloaded one time which my Kaspersky anti virus detected and removed but I am not too sure if it was that file , However if it was that malware, would it have affected my PC till now since the day it is running with 'pca'? Though I still use this antivirus I think It was just a trace of it?