I have a problem with Leopard. I picked up a copy earlier today. whenever I put in the Leopard disk to the iMac, it spins up, stops, the laser fumbles around, and then it spits out the disk. I tried it on both my PowerBook and a MacBook, and they both read it fine. The iMac seems to read other disks fine. It has a matshita drive. It is a early 2006 iMac 17 inch with 1 GB RAM. 