Would I be best off to format some of the 160gb as FAT32 (so if I ever need Windows again I can use the data on it) and transfer over my data like that?
No problem. I have almost the same configuration, but with Debian, with the partition for data as FAT32 so I can see it from Linux and Windows. To see it from Linux you have to add a line in the file "/etc/fstab":
/dev/hdYX /mnt/data vfat auto,exec,user,rw,nosuid,umask=0 0 0
Change de Y and X in the "/dev/hdYX" field depending on your HD and partition. You can know your HDs structure with the comand "fdisk -l /dev/hda" and "fdisk -l /dev/hdb".
The "/mnt/data" field is the mounting point in the tree (you can change it).
vfat because of FAT32.
I don't really remember the rest but I can do everything so I wouldn't change it.
I've done this with Fedora Core 4 and guess it will work with SUSE.