I found this in a few different places around the 'net - hopefully it's helpful:

How to Automate Advanced Restart Options for Dual-Boot Configurations

This article describes how to automate advanced restart options for dual-boot configurations. If your computer is configured to dual-boot to either Windows XP or Windows 2000, the process to boot to the other operating system can be slow.

For example, if you want to reboot into Safe mode under either operating system, you have to watch the computer reboot, monitor the power-on self tests and various BIOS messages, select which operating system you want to boot with from the Startup menu, and then press F8 at the exact moment to enable the Advanced Boot menu. You can select your Safe mode boot options from the Advanced Boot menu.

This article describes a method you can use to create a custom Advanced Restart menu on the Start menu. You can use the Advanced Restart menu to preselect advanced restart options before you restart your computer. After you select your restart options, you are prompted to restart, and your computer starts with your preselected options, and does not require that you press any keys during startup.

IMPORTANT: The following procedure assumes that you have a dual-boot configuration with Windows XP and Windows 2000. Also, although the following procedure works correctly, Microsoft does not support the following procedure:

• Create a shortcut that is named Advanced Restart on the Windows XP Start menu.
• For the target path, use the msconfig -4 command. For example, you might use the c:\windows\pchealth\helpctr\binaries\msconfig.exe -4 command.
  
• Create the same shortcut with the same path for the Windows 2000 Start menu. This shortcut on the Windows 2000 Start menu should use the path to the Msconfig.exe tool in the Windows XP folder.

The "Advanced Restart" shortcut you created starts Msconfig.exe with a switch that loads the Boot.ini file properties dialog box. From this dialog box, you can select the default operating system, Safe mode options, and other advanced boot options. After you select the restart options and press OK, you are prompted to restart your computer. When your computer restarts, it starts with the options you previously selected, and does not require that you press any keys during startup.

Note: When you boot into Windows XP or Windows 2000 after you use Msconfig.exe, Msconfig.exe automatically starts in diagnostic mode.