Most AV scanners are much of a muchness these days - I manage a McAfee EPO infrastructure for a large financial org and they've always had definitions added by the end of Day Zero of any exploit... best you can hope for really. Far as I can see Kaspersky and most of the other big names manage the same, so they'll all offer more-or-less the same protection from viruses (i.e. you'll be protected after about 4 or 5 hours of an attack being in the wild).... which is something, but isn't a huge amount given the potential speed an exploit can spread these days.

If you want to *actually* be secure, you're better moving away from blacklist products like traditional AV (Blacklist i.e. it holds a list of known viruses, blocks them and allows everything else) towards Whitelisting products like Bit9 Defender which learn your machine's usual behaviour then block everything else. Better for servers than workstations really - for your home PC I'd suggest a decent AV scanner, a decent software firewall and, most importantly, a strict regime of not acting like a dickhead on the Internet.