Hello everybody. I have a macmini dual core intel running on 10.4.11 and need to upgrade to 10.5. However I am having trouble obtaining installation discs. I have bought discs from Internet with the supplier saying that the discs would install ok. Not so, the discs read on them" for mac computers 10.5.6 osx and failed to install. I have since found they were for MacBook . Although there are mac computers in the household they all pretty recent. What do I need to purchase and where from, as I am at a complete loss over the terminology