I had installed both Windows 7 and Open SUSE, booting with grub, but recently I decided to erase the partition with Windows and just keep Open SUSE.
My problem is that the entrance of Windows is still in grub and I want to remove it, how can I do so?
It depends.
If you are using legacy grub (sometimes called “grub1”), then
Yast → bootloader
and you can edit the menu. Or, for opensuse 13.2, you would need to manually edit “/boot/grub/menu.lst”.
If you are using grub2, then:
# grub2-mkconfig -c /boot/grub2/grub.cfg
should do what you want.
grub2-mkconfig -**o** /boot/grub2/grub.cfg
or
update-bootloader --refresh