A Setup for Inexperienced Users
Inexperienced users usually like programs that they can "set and forget". This often decreases the security though. We need something quiet, yet strong.
GeSWall is the first application I recommend. After install, it doesn't require customizing. Because it does not bombard people with alerts and notifications, it is exceptionally easy to use while still providing great protection. If you want even fewer notifications, consider buying the Profession Version which comes with preconfigured rules.
Comodo Internet Security (CIS) has a reputation for giving lots of alerts. Although Comodo has made efforts to reduce the number, it still is generally not user friendly. If you don't want to be bothered by alerts, try these instructions (click on the links with the camera to see a picture):
This is called "Parent Mode". Now, all new files (except for files digitally certified with a trusted vendor's certificate) on the computer will not be allowed to do any actions that CIS detects. Files already on the computer are allowed to do anything. In addition to being an effective method of securing your PC, it is also very useful for public computers and computers that kids are using.
You may also consider getting the a Pro license (about $39 USD) for CIS, which includes remote support to help you with common problems.