Please keep in mind, that Avira won't work for you, if you have installed (like me), linux like software in your windows installation (eg. Redhat's cygwin1.dll).
Comodo av, don't has and won't has a big virus database while is in its beta stage. Better to keep your distances from it, unless ofcourse you want to participate in beta testing.
Rootkit detection software, you can find there: http://www.antirootkit.com/software/index.htm
My personal opinion (please don't get mad, just my personal opinion), is not to depend in site reviews for helping you at your personal research. I think is better reading individual users experiences.
PS. I have here installed AVG and I'm quite satisfied from it, but I'm sure you can find other good solutions as well.
Greetings!!!