I'm going to roll the opposite way and say put the OS on Sata2 and the pictures on sata3. The os boots in 30 seconds and then you're pretty much done with it whereas you spend hours up[on hours working with your pictures (videos in my case) so I'd much rather have them loading/saving faster rather than knocking off another second or two on windows loading.
ps - a 960gb ssd.. I'm jealous! LoL