Installing vanilla anti-virus software on your system just won’t cut the ice when it comes to firewall protection.
Simply put, you need more weapons (shields?) in your arsenal. To keep internet threats at bay, you need protection at the most basic level. It won't be difficult if you have the right tools. If you are wondering about which firewall application to choose among the mind-bogglying array of products out there, here's some help. These are all good choices for Internet security, and all of them are either free or have a trial version for you to try.
The Shield Firewall 5.0: One of the newest kids on the block, The Shield Firewall is a great value. For less than $20 USD, this firewall manages to rack up more features than say, Zone Alarm Pro. Shield Firewall provided a glitch-free installation and is easy to use. Surprising light on system resources, it also comes with free phone and email support. Better yet, there's there's a lifetime license - buy it once and use it for as long as you need.