My old clamshell iBook seems to be running very slow suddenly, I have to wait for typing to catch up with me and in this chatroom I go in, the chat screen keeps filling in and changing to same colour as background so I cant read what people have sent into room or and all buttons disappear until I run cursor over where they were! It doesnt do this when I go in same room on iMac. It didnt used to do it on the iBook either! is it just getting old and needs replacing? Think mine was made in 2000, so is about 8 years old. How do I do things like disk defragment or see how much hard drive and memory is been used? I wondered if it was maybe full? Any ideas?