[Felix12g]

Are you letting your computer shut down completely first? It'll be fine if you actually let your hard drives spin down and your computer shut down naturally. If you're just yanking the cables out of the back then yes, that's bad for your hard drives. If you asked this before 2000 I'd probably want to smack you, but these days your harddrive is about the only thing that will really get hurt. It's most definitely not good for your computer and you may start running into corrupted files but hardware wise beyond the drives you should be safe.

If your hardware isn't cooling down sufficiently after shutting down then that sounds like you've got an airflow problem, the trickle of power that's still being used by the computer is nowhere near enough to overheat a video card. And unless you've got a faulty power supply it should be drawing almost nothing.