yeticorn :
I know everyone has their preferences, but if you're going to slam a certain product at least have independent whitepapers or something to back up any claims made.
OP - As stated, Windows Defender is adequate and recommended for the average user.
Have you seriously not read any independent lab testing? It's a widely known fact that MSE has below industry standard protection. Of all things, that's the one that shouldn't require proof... but...
AV Test- Windows Defender test results
Just about anyone who looks at independent lab testing would know that MSE is not up to standards. Not to mention, if you're going to request evidence, at least take five minutes to research something yourself, so you can have your own research to back up or refute a point that is made; it helps everyone out, including yourself.
Again, MSE/Defender is
absolutely NOT recommended for any user. If you're a very advanced user, you could consider using MSE, but there are better tools for advanced users as it is... so MSE is a moot point at best. If anything, MSE is probably the biggest waste of software, quite honestly. The reason I say that is because Microsoft obviously doesn't invest in quality protection measures, and they constantly fall behind in lab testing. Microsoft needs to focus on their other products more, like the cellphone branch they just recently canned.
Also, a minor correction for you: the OP never stated that MSE was adequate; that was the first reply... but I just figured I'd keep giving you a hard time while I was at it. Happy?
To the actual OP- any of the free AV solutions I've offered you are going to be sufficient for a basic free AV, will out perform MSE any day (even on bad days), and they will have a lower impact on system performance than MSE. Check out
AV-Comparatives if you want to see the actual lab tests. I've been doing freelance computer repairs, malware/virus removal, data recovery, and custom Windows installations for a good few years, and have always been trying to keep up with the hacker community for attack prevention... MSE is terrible, and there's plenty of publications/labs that can support that. Not to mention, you're free to run the tests yourself (though I don't recommend doing so on your main computer, or without any knowledge of how to run a test).
Check my signature for a tutorial on how to pick an AV, or look around this section of the forums... there's plenty of recent, and relevant, information that will help you pick out a decent AV. Feel free to do some research or ask for some sources for lab test information.