First PC i could touch was an ibm or similar clone with ms-dos (don't know which version) in school. We used floopy disks to save are homework (both the 3.5 and the other much bigger, 5.x? inches, don't remember...). We learned and practice some basic commands like cd cd.. dir, etc and finally after that, teacher let us play games: it was td3, gorilla and others. Also i remember that just 1 of those computers in that time in school were on color, so we had to make turns to use it and play td3 with it... :P