Windows Defender is the best choice for Windows 10 since it is built into the code and has access to areas of core Windows components that 3rd party software cannot access. You may also run 3rd party software on an on-demand option. Never run two different antivirus programs in real-time scanning as they will interfere with one another and cause you system problems. Most modern AV software disables itself when you try to install another or it simply prevents the installation of another program until you uninstall the first. I have personally used Iolo’s System Mechanic for many years and am quite happy with it. I also like Malware Bytes anti-malware. It is a good “free” option. If you look at PC World or other Pc related publications you will find their yearly round up with recommendations for what is the “best of class” at the time of publishing. Stay away from Kaspersky as they are currently under scrutiny for data gathering/privacy concerns.

Your best AV protection is good data awareness practices.

Don’t open attachments from people you don’t know or trust.

Don’t trust java or adobe flash, but if you must use them keep them up to date.

Keep all programs patched and up to date – Heimdal is an excellent way to do this. (It is a 2nd gen anti-malware solution which is second to none in helping keep you safe.

Listen to Steve Gibson’s Security Now! Podcast. It’s available On iTunes courtesy of TWIT.