Geoff, With the Gnome version of OpenSuse, open the menu at the bottom left and go to control center. You will find Yast at the bottom of the control center page.

The layout of the Yast main page is different in Gnome but you will find a system section and the partitioner in this section. Not all the Gnome set up interfaces are the same (eg. the software manager is different) but the partitioner is identical to the KDE Yast one (as of course is /etc/fstab - that would be the same with ubuntu and fedora too).


---
From your previous post it seems you might have more than PC running Windows. You might like to look at Samba at some point.