I have a laptop triple booted with Opensuse 11.1,XP Pro and Windows Vista. Now I want to overwrite the XP partition with Windows 7. Currently grub is the first bootloader , then once I choose Windows in grub , the Windows bootloader shows either Xp or Vista. What would happen if i install Windows 7 on the Xp partition? Would i be able to boot into any OS ? What changes do i have to make to grub config?
When I installed Windows 7 on a box that also had Ubuntu and XP, it took over the MBR, replacing Grub, and I had to reinstall Grub. Windows 7's installer is generally smart enough to include former versions (Vista in your case) in its own boot menu, or you could boot directly from Grub.
Do you need detailed instructions on how to create a menu.lst file?
When having a mixed environment like this, I think that it is better to let the mbr act how it was meant to originally, ie just choosing the partition to boot from.
If you have a Linux partition that is a primary partition, install grub there. Opensuse will also write some real mbr code to the mbr of the disk and make the partition with grub on it active for boot purposes if you tick the appropriate boxes.
When Windows the Windows installation process overwrites the mbr, the only effect that then matters is that it changes the active partition to the partition where it puts its own bootloader, and all you have to do to get grub to boot is to change it back. This is not as easy as it should be because of a bug in disk management which will not let you mark a non-Windows partition as active, you will have to use the Windows command line diskpart utility.