1.if you have an ATX mobo/power supply, yes you can just take the wire of th pc's pushbotton and hook it up to the switch or trace the wire from the pc switch to the mobo and make a wire for it.
2. yes you can just take the pc power supply. Make sure what voltage the buld accepts and use the pc's red wire for 5volts or the yellow wire for 12volts.
Same goes for you LIGHTS.