Hmm... both of my children have been using Linux since they were born, and they still are. As a matter of fact my son was just the other day mentioning that all of his friends are jealous about his computer because of Compiz. Also most of his Windows using mates have not been able to configure Enemy Territory game, which he thinks is because of "ridiculous" windows OS. My son is not yet in highschool but I'm sure he will stick with Linux by the time he's there. And the same applies for my daughter.

My 77 years old father uses Linux without problems. He does internet browsing, email and digi-photos with it and he's very happy with Linux. The Linux-brand he's using is Kubuntu.