Help with new mac setup.

Just bought a new 2010 base Quadcore. I am adding 12 gigs of ram and an extra 1 terabyte drive from OWC.
This mac will have four different users all with different uses.
My wife will mainly be using it for music notation using Sibelius and for garageband and eventually Logic. also Iphoto.
My one son will be using it for 2d/3d animation with Blender and design work with photoshop and Illustrator and game design and Playing a lot of WOW.
My other son will be taking Computer aided drafting an design at a tech school.
I do a little bit of everything.
On my old g4 I had a separate partition for each person and the system was on it's own drive. Music and photos were on another drive.
I was wondering what is the most efficient way to set up my 2 drives for speed and file management.

Thanks
tes64