a) Oops.
I only ever charged after it died, or an hour or so once the red light came on.
c) Overnight, while I sleep. I have to assume the leaving it plugged in after it finishes charging has no effect on the battery at all, seeing how there is no current running through it.
But I still notice it dying pretty quickly these days... should I get a new battery (easy install, and I can always keep the other one as a spare if I need one, for some reason) or just go get a DS Lite?
$20 for a battery, be able to play GBA games without sticking out so much but still have a few dead pixels, or $150 for new everything, brighter and more colorful screens, but have GBA games stick out... decisions, decisions.