I just got each of my daughters a 2008 iMac, one is a 2.4GHz and one is a 2.66GHz. I upgraded both to 4GB of RAM, 240GB Sandisk SSD Plus ($60 woo hoo) and both on El Capitan so they have all the updates. They are mainly going to use them for music, Plex, radio and Microsoft Office. I do want to let them have a browser so they can look up stuff on the internet because they are curious (they are six and eight) but I don't want them to be able to go just anywhere or have YouTube. Is there a OS X browser that can do this for me? Also how can I disable Safari so only I can use it when I need to do something online on their computers?