No, you’re not having a déjà vu, this is my second post about GRUB2/BURG support for KDM which shows up in PlanetKDE. I am sorry to abuse the planet for publicity, but I have seen quite a bit of confusion as to how KDE should be configured in order to interface with GRUB2/BURG and I would like to get some things straight.
What follows is a step-by-step guide describing how to configure KDE in order to automatically select a GRUB2/BURG entry other than the default when rebooting:
Shutdown Dialog
If you are a GRUB2 user skip the BURG instructions and vice versa.
Step 1. Inform GRUB2/BURG that you plan to use this feature:
GRUB2 instructions:
Open /etc/default/grub in the text editor of your preference (as root) and add the following:
GRUB_DEFAULT=saved
In case a GRUB_DEFAULT option already exists, just set it to “saved”.
BURG instructions:
Edit /etc/default/burg instead. The variable name is the same (GRUB_DEFAULT).
Step 2. Update your GRUB2/BURG menu file:
GRUB2 instructions:
The menu configuration file must contain set default=”${saved_entry}”. You are highly discouraged to manually edit this file, so execute the following command (as root):
grub-mkconfig -o /boot/grub/grub.cfg
Please note that some distributions (i.e. Fedora, Gentoo, Mandriva, openSUSE) use a slightly different naming scheme for GRUB2. So you’d have to adjust the above to the following:
grub2-mkconfig -o /boot/grub2/grub.cfg
BURG instructions:
BURG users should execute the following command (as root):
burg-mkconfig -o /boot/burg/burg.cfg
Step 3. Inform KDE that you are using GRUB2/BURG:
GRUB2/BURG instructions:
Select “Grub2″ as your bootloader under “System Settings > Login Screen > Shutdown > Boot manager”.
Step 4. Create symlinks:
GRUB2 instructions:
This step only applies to Fedora/Gentoo/Mandriva/openSUSE (or any other distribution which uses /boot/grub2 instead of /boot/grub)! If this is not the case for you, skip it.
Execute the following commands (as root):
mkdir /boot/grub
ln -s /boot/grub2/grub.cfg /boot/grub/grub.cfg
ln -s /sbin/grub2-reboot /sbin/grub-reboot
In the above commands replace /sbin/ with wherever the grub2-reboot binary is installed. You can easily determine this with “which grub2-reboot”.
BURG instructions:
Execute the following commands (as root):
mkdir /boot/grub
ln -s /boot/burg/burg.cfg /boot/grub/grub.cfg
ln -s /sbin/burg-reboot /sbin/grub-reboot
Same rule as above applies here: if the burg-reboot binary is not located under /sbin/, locate it with “which burg-reboot”.
Step 5. Reboot!
That’s it; you’re done! Now either reboot or restart KDM (something like “/etc/init.d/kdm restart”) and you’re all set 
As a side note, GRUB2 Editor (supports BURG) automatically adjusts your configuration to the above. If you’re using it, you won’t have to do anything at all (other than step 4 for the distributions affected and BURG installations).
Feel free to link to this post in linux forums as a reference. All of the above refer to KDE >= 4.7.
Edit #1: Instructions updated to include BURG.
Edit #2: Fix text formatting.
