Linux Mint Forums

There is no need for anti virus, but if you dual boot with Win you might install an on demand scanner to secure your windows.
There is no need for a firewall if you're behind a router as a lot of people are. But if you're connected directly to the net you may need one. Firestarter could be a good alternative

You already are behind a firewall called iptables and have no open ports by default, a frontend for iptables is called "firestarter" as mentioned above. So there is no need for a huge install-button, since the firewall is already installed.

There is others that can explain this better than me i am sure, but the way Linux is set up with root (sudo) and user, a virus can not do much damage on your system unless it is written for Linux and you execute it yourself and give it clearance with your password. There is malicious code , see: http://ubuntuforums.org/announcement.php?f=13 ,but that is also something you have to put in yourself.
As Linux grows more popular there will probaly be more viruses for it, but i think the XP way of getting a virus by visiting a website or opening a mail is nothing you have to worry about.

I would not loose any sleep over viruses if i were you, give Linux some more time and you will forget all about it (until you hear friends at work discussing wich virusprograms is the best and think: oh yes i used to be there;-))

Found an article about a Mac virus pretending to be a multimedia codec.
http://news.bbc.co.uk/1/hi/technology/7079777.stm

That virus was for Mac, but something similar could happen with any *nix system.
The way it worked shows how you yourself has to grant it access to your machine by typing your password.
But if you stick to the official Mint and Ubuntu repositories, these kind of things is of no concern to you.