I heard hibernate can be damaging to your computer... but it seems so much more efficient than having all my stuff saved to a certain place and having to re-open everything... And then deleting the saved items because you don't need them...

Shut downs are great. Energy bill goes down a bit. I do remember reading somewhere that it can damage your computer if you do it too much.

And then sleep mode. I found sleep mode to the be most pointless thing ever for my computer. o3o

Blaaah. Just give me your backed up opinions. D:
I want to:

1. Not kill my computer's hard drive
   
2. Save energy
   
3. Save where I left off on my computer
   

Yeah. In that order. :c

Sleep mode is like a quick Hibernate. it saves most stuff in the RAM until awakened. there is little power flow to keep the ram working. {laptops go anywhere from 4-12 hours approx. in sleep on one charge}

Hibernate is a safer sleep mode. It saves everything to your HDD. It takes about 10-20% longer than going into and out of sleep mode, depending on PC type. there is no power flowing through the PC. {laptops get approx. 10 hours to as much as a week on one battery charge}

Shutdown is a complete shut down - recommended if you a big powerful desktop