Normally they have Windows 9x, Windows NT/2K/XP and Linux.
Thus, the 1st disk just have the boot partition for each OS (and multiple partitions for Linux). Programs, data and work partitions are all in the 2nd disk.
I'm right now, setting up a computer to take home that will be my computer. It's nothing impressive (PIII@1000, 2 disks 20G and 40G IDE drives, and a RIVA TNT2 video card with TV IN/OUT) but will enable me to work at home just like I work here.
These last days have been just with installation work and a lot has been done already but much more is still waiting to be completed.
Well, back to work.