Laptop freezing every time I confirm/cancel something related to Avast

I got Avast yesterday and since then it’s been fine, over the last hour every time I cancel or confirm something to do with Avast my whole laptop completely freezes, it may not be just avast but it seems like it’s only when Avast is touched it freezes.
Any advice/answers would be very much appreciated and please tell me if you need more information. Thank you in-advance anyone!

I was able to do a Malwarebytes quick scan without it freezing and that came up with nothing infected.

I have Malwarebytes, and Privatefirewall 7.0 installed and of course Avast (which hasn’t alerted me to anything and I can’t do a scan because it freezes most of the time)

EDIT: It may not be a virus/malware but what could cause the entire system to freeze when confirming anything to do with Avast?

what AV did you use before avast?
did you uninstall it before installing avast?
did you use the vendors removal tool to clear any leftover files that may conflict?

tools here. http://singularlabs.com/uninstallers/security-software/

I had Norton 360 and I did use their removal tool from their website to uninstall it.