ok. bear with me, i've never had a mac or messed with one too much. so i bought a used cheap imac g3 to mess around with. yes its ancient. it was practically free. the store wiped it, so no os. i have my os x discs. i put disc 1 in and it doesn't boot the disc on startup, and i try pressing c or command shift option delete but still no boot. am i doing something wrong? when exactly do i press c, do i hold it? all that comes up is a gray screen and a small folder with the mac face switching to a question mark.