From what I've read, Microsoft Security Essentials have really fallen behind since 2010 - in fact, I don't think Microsoft even updates it anymore. Norton and McAfee have taken a dive in recent years, too.
Personally, I'm using ZoneAlarm Extreme Edition - costs about $39.99 for an annual subscription. It works very passively in the background, and does a fairly decent job of monitoring/cleaning my system. It even has a "gaming mode" that completely takes away pop-up notifications, if viruses are found.
It works well for me, and I'd recommend it. It even has 30 day trail period so you can test it out yourself.
The ratings for ZA are pretty average, but I don't pay attention to editorials anymore, since I suspect a lot of editors are being bought out by the bigger corporations (and it's very telling when McAfee and Norton are given good editorial reviews, but horrible reviews from actual users). The user reviews are what matters to me the most, and ZA has generally garnered good feedback around the net.