There's a long and short answer to that, bearing in mind multiple machines running in a home and home-office environment, on a range of OS's including Windows 2000, Ubuntu and, yes, Win 7.
But the relavant bit for you, which is the Win 7 machines, is ..... wait for it .... Comodo.
I've used a variety over the years, both free and paid-for, and currently, and for several years, I prefer Comodo.
But there's a thing. In my view, there's no one perfect, ideal 'best' firewall.
Every product has to try to hit a blend between security and versatility on the one hand, and user friendliness on the other. If you have a product that is too locked down and cannot be adjusted, it's restrictive in what it allows, but that might be exactly what suits some users .... whether they know it or not.
But it'll be useless to others.
And if a product is very versatile, it can also be complicated to set up. Show most users a set of firewall rules and their eyes will glaze over in nanoseconds at the notion of TCP/IP, UDP, ports, and so on.
And, if you have a versatile product in the hands of someone that doesn't understand it, then it is SO easy for them to leave it set so insecurely that it might as well not be there, as it gives a false sense of security.
It's like having your front door replaced by a vault door that would do Fort Know proud, with a 50-digit numerical code to open it, then scribbling the code on a bit of paper pinned up by the door because the kids can't get in the house if you don't.
Comodo suits ME. I'm a fairly PC and security literate guy, but I'm no expert. Comodo hits the right balance for me. For anyone else .... who knows.
