Ok I have been working on windows pc's for the last 10 years. I am employed as an IT tech and know pc's farely well. I'm not saying I am a know it all but I just wanted to give some background. I know next to nothing about macs and would like to learn. My girlfriend has an older model G5. I would like to buy maybe a mac mini to understand how the os and applications work. Where can I get guides on loading the os and making a back up? Thanks.