keylogger virus spyware malware help

I got an email that came straight to my inbox and they listed one of my passwords (which i have now changed on all sites I can think of), saying that they had put malware and keyloggers and stuff on xvideos (a porn site if you didnt know) and that theyd captured video from the webcam and...

so my anti-keylogger tester (atkl) found key logger ,when pressed buttons in order to test .... how can i be sure it's true and how can i peremantaly delete and prevent any key loggers or other spyware on my pc ??? btw had some freezes and tryed restart explorer exe but wasnt unable to end this...