I bought my kids a PC and installed 12.04 (Unity) on it. The bottom line is, I want my children to use the computer unsupervised while I have confidence they cannot access anything inappropriate.

What I have looked at:

I was looking at Scrubit which allows me configure my wifi router but this solution would also affect my other PC and mobile devices. This is not feasible as I just want the solution to work on one PC. I also did some Google searches and came across Nanny (it seems to look the part). My experience of OSS is that the best solutions frequently never appear first on a Google search list so my question is very specific.

I want to leverage your knowledge and experience to understand “What is the best way to restrict adult content on 12.04 LTS” as this is important to me. Please don't answer this question "try this or that", then give me some PPA, I am looking for knowledge and experience from someone in my situation.

Thanks in advance