When I try to turn it on, it freezes on the "starting windows" screen.
Ordinarily there should be no need for most people to make use of the program, but it comes in handy when the standard uninstallation process for AVG fails, or to help overcome problems with installing a newer version of the antivirus tool.
There are two version of the removal tools available - one for 32- and one for 64-bit Windows - so ensure that you are using the relevant version.
AVG 2016: How to remove AVG Shredder from the Context Menu?
What happened here is you’ve visited AVG website to download free antivirus and ended up installing AVG IS with AVG Zen, which you’ve not expected or don’t want.
In Command prompt, go to the folder where resides (probably Windows\System32\drivers) and rename the file. If you are able to boot into Windows, uninstall AVG (download the uninstaller from AVG site). Apparently my PC was freezing everytime I tried to boot something because of my Onboard LAN.