Hey all, I'm new to Mac, brand new. I have always owned PCs and Android phones. Well, my wife surprised me with the iPhone 5, I liked it so much I started looking for a cheap Mac to see how I like the OS. I just got a 2006-2007? White iMac, and I had a few questions. Let me preface by saying that I know the bare minimum and basics about computers, so I apologize in advance if I say something terribly ignorant. Ok, first: I notice the screen gets pixelated in small areas, or starts having a torn look, what is it and how do I fix it? Second: I want to bring this computer up to date of I can, do my first thought is "I need a faster processor, more memory/RAM, and a bigger hard drive". Well, here is where I got confused. I was asking my friend (a PC guru) about replacing the processor in my Mac. He says it can't be done. ****. He tells me that upgrading the memory is super easy, though, and if I do so, it should speed it up a bit. Forgive me if I sound ignorant, but I thought my processor determined my speed, not my memory, so if I upgrade to 4gb ram, but have the exact same processor, I shouldn't see any "speed" difference. Is this not true? He also said replacing the hard drive isn't worth messing with. Any help is appreciated.