You need your Vista DVD though, because once you format your other partion GRUB is still trying to load, it cant because most of GRUB was on the OpenSUSE partition. This will cause Windows not to load. Once you delete the other partition though, you can put in your windows DVD and open up the recovery console and type FIXMBR. Once its done, Reboot. Your Linux installation should be deleted and your Windows should load properly.
If you don't know how to get to the recovery visit the site below.
http://helpdeskgeek.com/how-to/fix-mbr-xp-vista/