» Sat Feb 19, 2011 3:13 am
Never unplug the console unless it is your last resort. If the power-off is not working, walk away for 20minutes and try again before unplugging it. A sudden negative surge in power can easily kill a piece of hardware as sensitive as the xbox360, and every time you do, you're rolling a dice where 4 of the 6 sides result in "You're f*cked".
Ejecting the disc during a freeze does not always work. Sometimes it does, and it certainly doesn't hurt to try, especially if you're considering pulling the power cord out. One telltale sign that using the power button itself doesn't hurt the console, is if you open the disc tray, and power-off the console without closing it, the console will power off, and the disc tray will close (Indicating it still is receiving stand-by power), however if you unplug it in the same situation, the tray will remain open, indicating no power is being brought to the console, and the surge at the moment of disconnect, could have overwhelmed the hardware.
Also, if possible, connect a 360 (And any sensitive electronics) to a protector with a voltage stabilizer(Not a standard surge-protector, for some reason these can be a liability with the 360) and preferably a battery draw backup, that allows a safe shutdown instead of a sudden cease in power. This is especially important if you live in sunny California during the summer.
Oh, and to answer some of your questions.
-> Yes the console will properly stop the disc from spinning. When you open the tray and notice the delay from open-close and the console light is flashing, that's the drive resetting to Idle and stopping any spinning disc in there.
-> Installing to the hard drive is always to your benefit. A hard drive has many less points of failure than the complicated disc-reading process, and it is also quieter and runs cooler. If you pop the disc out with the game installed to hard drive, it will still put you to the dashboard, since the disc is still required for DRM purposes (The console will read the lead-in at startup, but nothing else) having the disc in the tray and console is still a necessity.
-> Overall, opening the disc drive is the second best way to shutdown the console, and the best option, if the game is frozen and it works in the first place, to reset the console. Under normal circumstances, using the xboxguide software to return to the dashboard is the best way to idle the console, opening the disc drive forces this with a slightly more stern hand, powering off the console naturally (Through the software guide or from pushing the button) has a slight chance to cause hardware damage, only if something is already compromised. Pulling the plug, or otherwise suddenly killing the power is never a good solution outside of a last resort scenario, and inadvisable in all circumstances.