I've got a few other things on this PC that run on start-up and it's a pain trying to shut down all the non-essential applications before dumping video onto it.
If these items are in the starup folder simply press and hold down the shift key when you log in / power on and keep it preesed until the desktop is displayed -- nothing will start then. (A bit like "autoplay" - if you hold the shift key down when you put a CD in the drive it won't, erm, autoplay
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