Stop clicking "next"
Don't ever do a default install, especially of a free product! All you have to do is un-check the options you don't want, like the toolbar, and there will be no popup ads or search data to be sold.
AVG works fine for a free product. Sure, the attempts to get you to move to the paid version (even the free trial) are a pain when you just want the free product. No AV catches everything. Any decent malware author tests their new creation against all the main scanners before releasing it.
There's no AV company that hasn't had bad definitions bork a system file. There isn't an AV, free or paid, that I haven't seen "protecting" a horribly infected machine. They are just one tool, not a total immunization!
Biting the hand that feeds IT
