The data for the Grub boot menu are in /boot/grub/menu.lst
With SuSE 8.1, you could start yast2 and select the module System - bootloader configuration. This yast2 module basically provides a graphical frontend for editing the configuration of grub. I'd suggest
1. Modify current configuration
2. Leave what is already selected for the place where grub is installed (though you may consider changing this if it turns out it doesn't work otherwise)
3. go on with "Next" again (screen with global bootloader properties)
Then a list of the sections is displayed, there you can choose Add - Add DOS/Windows section
Alternatively you could also edit /boot/grub/menu.lst (and grub.conf, if necessary) directly by choosing "Expert manual configuration", but I don't know the exact syntax of entries in the bootloader menu, and it is probably easier to try the graphical frontend first.
As far as I know, it is not necessary (nor possible) to indicate the type of the file system (NTFS in that case), grub just hands over control in that case.