If you're worried about the security of your system, you need an application like AhnLab V3 Internet Security.
AhnLab V3 Internet Security is a comprehensive security tool that protects your computer from any kind of online threat, including viruses, worms, hackers, Trojans, spam and phishing. The program features a nicely designed interface with different sections for the specifically protected areas: system, network, content and email, as well as some system tweaking options.
Though this may all sound too complicated for you, the good thing about AhnLab V3 Internet Security is that it's quite easy to use, includes links to the correspondent settings menu on each separate function and is also thoroughly documented.
In a way AhnLab V3 Internet Security reminds me of the Windows Security Center, as you can control pretty much all security options from a single, centralized interface. That said, this is the kind of application you need to try it for a certain period of time in order to fully test its performances.
AhnLab V3 Internet Security protects your computer against all sorts of online threats.