My first macs were all family computers: performa of some sort. We had that for some time, and eventually we upgraded to the G3 iMac, and a G4 eMac after that. In school the first computers in the classroom was in 4th grade, the lab consisted of a bunch of qudras and early power pc machines, and a few windows 95 boxes. Middle school had a lab full of the same power PC machines. High-school saw iMacs in pretty much every classroom. This year my university bought new computers for pretty much every lab, one half of the lab being 27'' iMacs and the other half being some Dell box with core i-7s and u2711 monitors.
I personally bought MY first mac when I moved out of my parents house. it was a 2.8 or 3.02 something 24'' iMac. I loved it dearly. I also had a black macbook. Those were my last 2 actual mac purchases. I built my first hack on the LGA775 platform and haven't looked back since. I saved my brothers 2007 macbook from the garbage, replaced the HDD and RAM, cleaned it up, installed Lion on it and she runs just fine.
Oh, and I rebuilt a g4 800 something tower off Craigslist a few years back I have running system 9. I use it for old games n such... Harry the Handsome Executive, Marathon, Gone Fishing, Bonk Heads...