just bought a imac g3 333mhz with 96 memory and 6 gig hardrive,has 8.6 operating system,bought online,and was from a high school so i think they blocked out certain applications,when i try to do anything to fix it it restarts,i want to update up to 9.1 or maybe turn restrictions off, whats the easy way to do this,can a 9.1 restore disk do it,or is there a certain way to turn off restrictions thanks