Over the past several months my Mac (iMac G5) has been acting up. Programs began to crash and load / close very slowly, opening or saving a large file could take up to 3 minutes, the fan would be working overtime, the external firewire drive would drag (and I do mean drag). As time went on, my keyboard wouldn't be recognized on boot-up and I'd have to unplug/plug it back in every time (I blamed the Microsh*t keyboard). Then last Friday the damn thing booted all the way to the desktop then it...