Pc user scratchin his head over a mac, help me out

[mikesx4911]

Someone gave me a old iMac, I believe it was not working, it powers on but it never boots up to mac. i get to a blue screen and I can move the pointer around. I did a little research and it told me that a reload would fix this problem. So I put tiger in the tray and booted by pressing option, I boot off the cd and the little circle thing starts spinning and the apple logo is on the screen, but not long after the circle stop swirling. I have tried like 5 times, and now im stuck :*( What should I do?

 

[mikesx4911]

I think I figured it out lol. I press and held option key after hearing mac sound and let me boot off cd, now to wait for this long installation process and see what happens.