Always be careful what you install on your computer, and research what it is online. Especially if it's free. Software like this can put your online accounts at serious risk. In this day and age, emailing keystrokes unencrypted over the Internet is criminally negligent. There are much better ways to try and protect your children online with Windows Vista and higher having built in parental controls and numerous browser extensions/applications that can help you track what your children are doing online. But as an IT professional I've found that upfront discussions with kids about the dangers online coupled with the threat of active monitoring can do far more.

U.S. Police Are Giving Away Keylogging Software as a 'Safety' Measure
For years, local law enforcement agencies around the country have told parents that installing ComputerCOP software is the "first step" in protecting their children online.