Neither these two plists nor anything else in any user's home folder can be the cause of the problem. The system won't look in any user's home folder until after you log in, because until then it doesn't know which user is relevant.
But you're hanging before that, in the LoginWindow. The problem has to be with something encountered much earlier in the boot sequence than the things you're looking at.
Try unplugging all peripherals (except mouse and keyboard) before rebooting. USB devices, in particular, are known for causing bizarre startup problems. That includes USB hubs, so unplug those, but don't overlook FireWire devices.
If that lets you boot up, try adding things back a few at a time to narrow down the offending device.
A dead battery in a wireless keyboard would make a LoginWindow seem locked. Just a thought.
