Fedora finally took the leap to Grub2 with its latest release Fedora 16 Verne. So, if you want to change the boot order and default boot choice for your multiboot system this post tells you how you can do so. You no longer edit grub.conf or menu.lst files located in /boot/grub folder. Instead you just run a command.
To change the default boot option, you just need to change the GRUB_DEFAULT parameter. 0 represents the first entry, so if you want Windows to be your default boot option which is, say at, 5th position in the grub menu, then you just need to change the GRUB_DEFAULT value to 4 which you can do by running the following command as root
Then you can check what is the existing choice by running command
Finally you can update and remake grub.cfg using the following command
grub2-mkconfig -o /boot/grub2/grub.cfg
That should now change the default auto boot choice in Grub when you reboot.