Secure Virtual Machine Component

-In ‘simple terms,’ what is the Secure Virtual Machine Component?

-Should it be left off uninstalled or should it be installed?

Also known as NG.

Avast NG is a hardware based virtualization solution to provide more isolated test space. It is capable of running each Windows process in standalone safe virtualized environment (VM) and fully integrated to your desktop. Each process is executed in its own instance of VM, which means totally isolated from your other applications. This feature now powers Avast DeepScreen to improve better scanning of unknown programs (better detections)

If you use it or not is up to you to decide.

Eddy:

Does the ‘average’ user need to have it installed just for browsing the web and checking email?

It depends on how much safety “the average user” wants.

If you want to use it, first thing to do is checking if your system supports hardware virtualization.
If not, you can’t even use it.

Thanks.