Well, you could do the checking new mp3 files thing with filesync, and windows schedule manager.
In some bios's, you can set the computer to come on at a certain time. With windows schedule thingy, you can run a program at a certain time (run filesync a few minutes after your computer boots up) And, lastly, filesync can be setup to automatically copy any new files over to the car.
I don't know about the other things, though