On my Windows 10, up to now, only Windows Defender but I will soon use Windows Firewall Control to enhance the system security.
SMADAV (Indonesian Anti Virus) its very good at detecting autorun/shorcut virus from usb flash drives. very recommended Malwarebytes - this one is very popular its good at detecting malwares it has built in web protection (firewall) that blocks malware sites Windows Defender - 3rd layer of protection i'm using this 3 for nearly 3 years and still my system is virus free, yes they are compatible to each other even you plug all flash drive that full of virus it can't pass on this setup, sorry for the bad english hope this help !
Avast free [with correct settings it will not bother you at all] combined with MWB's, Time Freeze and Ccleaner is as good as anything. Non of these impact on performance, most of the others do, I wont sacrifice speed for any security program because I am not convinced that they provide the protection they claim. Its just a peace of mind thing, might be just as well off going commando. Its been said many times, the more dodgy sites you visit the better protection you require.
Or you can just disable autorun. reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" /v "NoDriveTypeAutorun" /t REG_DWORD /d "0xFF" /f reg add "HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" /v "NoDriveTypeAutorun" /t REG_DWORD /d "0xFF" /f Bitdefender Free is so far the lightest AV, I have found. It works and it is regularly updated. Along with Kaspersky inbuilt in the Yandex browser plus Sophos and OpenDNS protection, it is great.
Just stay away from Dr.Web as an install version, because it's worse than Norton and really hard to get rid-off again.
I use the CureIT from DrWeb once or twice a month for a full scan, but the fully DrWeb AV Version!! The CureIT need to be downloaded every time you like to use it, which is just fine for me! Have the best experiences that way!
Maybe your friend should stop installing freeware. Any browser issue like that I have seen is dodgy browser extensions or 3rd party software with freeware/3rd party software installers. They dont usually flag any AV. Solution is to uninstall the extension and any software that he doesn't recognise that is related, Kaspersky runs well been using it since 2008 some revisions have been hit and miss with resource usage but it does the job. I agree most internet problems come from negligence and if you are careful most AV's are not fully utilized and seem not needed. But they do the job for the unexpected stuff I do some heavy downloading and im careful, though a torrent the other month made my kaspersky go haywire, the network blocker didnt like the Sudden influx of Russian IPs in my Peer list and rightfully told me so. That and sometimes when I need to find some obscure software on deep web because even old links for it are down, it knows to flag that s**t up
People should start to read the (tricky) questions asked by nowadays installers of any "legal" spyware (including Chrome or W10 itself) tells what is going to happen, but no one reads such things. Worrying about the extensions, but starting with a crap browser is pointless. First use a decent browser like Vivaldi, Otter, Opera 11/12. Then start to be worried about the extensions. (Even the current Opera is enough at the time I'm writing, but the company was now acquired by a questionable Chinese company, the deal isn't yet finalized AFAIK). Chrome isn't just a privacy nightmare because of Google, it's also the most used browser nowadays, hence is a threats collector, just like IE6 was some years ago. As not being part of the flock is an advantage.