I am such a goon ! - I just bought (second hand) an iMac P4 800MHz to play with (my first Mac, so I was pretty excited to see what it could do better than my PC) - the lady I bought it from had upgraded from OS 9.? to OC X 10.3. Stupidly, I thought I would re-start it in the old OS, just to see what it was like and to see if the machine ran faster. Now it doesn't run at all! It boots up with a grey screen (and a little computer icon in the centre) then goes to a blue screen with the face logos and just sits, doing nothing with no response from mouse or key board. I tried 'control - option - PR' and the power re-set, both with no result. Have I just killed my machine? Can I get it back to start up the OS X 10.3 ? Hope someone can help me feel less of a goon! Mar.