I have heard excellent reviews of both Kaspersky and Trend Micro. Myself, I try to keep the number of different companies' products on my PC low, so I like to use a single software suite, and then supplement with one or two free (but good) software apps.
For years and years I have used Norton products, but I finally and unceremoniously dumped them in the past month. I have grown weary of the over-bloated Norton code that has come to invade every part of my system. It seems that the Norton developers do not understand the concept of efficiency.
Even starting up the computer with the latest version is a journey, as you have to wait a minute or two after everything loads just for it to say "Everything is working OK."
So I switched over the ZoneLabs (makers of ZoneAlarm) after researching the topic for a few weeks.
They make a product called "ZoneAlarm Security Suite" which I bought and installed. Every software product has its glitches and learning curve, but I have found ZoneAlarm to be much better than Norton in terms of performance and ease-of-use.
I like the ZoneAlarm control panel much better, as all the configuration options (and there are MANY of them) are all in one place. Keep in mind, you really have to spend some time understanding how it all fits together, but once you have mastered their interface you come to appreciate how much better it is than Norton.
One thing I do not like about ZoneAlarm Security Suite is that the security settings are set too high initially, so many web pages generate JavaScript errors. However, I think some of that has to do with the fact that they do not officially support IE7 yet, lucky me. For example, I went to Google and kept getting a JavaScript error window. It turns out that when Google senses IE7, it injects some extra code into the page so you can add Google to the new IE7 Search bar. (I don't know why they do that, since Google is already in there.)