For free, AVG looks pretty good. I'm using NOD 32 on three machines, and, it's keeping me out of trouble, and, has stopped a number of websites from nasty stuff.
Also, AdAware has found 451 'infections' mainly cookies installed by news websites, on my SO's computer. I've set both to notify on cookies, and, as a general rule, once you've gone through the setup process, I have no problems, and, the add sites that want to plant trackers are
blocked.
Dr Greg
PS
I showed one of my kids at school a couple years ago how to run ADAWARE, and, he had managed to install 2 hours of cookies. It took him two hours to run, check, and delete all the cookies that were installed on his computer. Main cause was going to music download websites.