I use AirSharing on my iPhone. It and other similar apps just use your phone as a drive on a wireless network, but then you can also view compatible files in the app as well (audio, video, mainstream documents, text). You can probably find a similar thing for free on the app store if you poke around.
Depending on your OS.... (1) right-click and change the color by clicking on the X under "Label" well it looks like that's the only way I can find to do that on 10.6, but I remember the option being about the same for all of the recent OS X versions.
I'm gonna venture a guess and say no. Everything is packed in so tight with laptops in general and this series in particular that any change under the hood will produce another logic board shape. You're in luck though, because the shell hasn't changed yet so feel free to buy the best Apple has to offer new (with all those extra wads of cash that are lying around all over the place...)
I think the drive is a lot more likely than the logic board, but I'm not sure what you mean by clicking. If the drive sounds like it's trying to spin up, but then suddenly stops - kind of a spin up and then spin down right away thing - the drive's either bad or the heads in the drive are stiff. Maybe they don't do this anymore but when i brought this problem to the people at the apple store a few years ago they gave it a few good shocks to see if that would loosen it up. If it hasn't beed used for a while I guess the heads in the drive can get a little stuck and a few good vertical blows (with a hand or on a leg) can loosen it up. Again, I'm pretty sure they gave it a few good knocks straight up and down in a vertical orientation. You don't want to crash the drive heads into the platters.
Like Rab said, you can try to boot up from the CD or another disk. Also, if you have another computer you can target disk the MacBook by plugging it in to another computer using a firewire cable and then holding down "t" when you turn the MacBook on (the other computer should be on already). This mode tells your hard drive to act as an external hard drive for the second computer, giving you access to all of your data, and an opportunity to reinstall the system software. If none of these work, your computer isn't getting to the point in the boot process where the system software really takes over and you probably have a hardware problem.
Battery life obviously depends on what you're using it for. Watching video or streaming lots of data will run the battery down quickly but I'll assume you're not doing that. If the iPod was new, the batterie's defective and Apple will replace it, but it sounds like you got it used. You're best bet is to replace the battery. Batteries wear out. Apple has some pretty comprehensive battery care instructions that I've found very useful but batteries will wear out eventually no matter what.