Answer to: Repurpose iPod firewire charger to work with Apple Dock USB devicesSorry, but probably not. If it doesn't already work (have you tried it?), then you won't be able to do much. Firewire uses unregulated power (~25v), which would fry most USB devices. If you have one of those white wall-bricks that you want to repurpose, the only thing you could do is wire up a 5v voltage regulator (lm7805) and a USB port. At that point, I'd just get a USB wall brick.
Answer to: The screen flickers, whites out and produces lines.Sounds like the LCD controller is dieing. The chips embedded in the screen's connectors are probably going bad. It isn't likely that you can repair the screen itself, you will probably have to replace the entire LCD module.