I use a 2.33Ghz MacBook Pro as the main workhorse for my production business, and I have Windows XP SP2 installed via Boot Camp to run some Windows-only software that I need to run natively (ie not in Fusion or Parallels). However, I soon tired of switching the boot disk from 10.5.2 to XP and back. So I came up with this little timesaver by putting shortcuts to the System Preferences Startup Disk panel (in OS X) and the Boot Camp Control Panel (in Windows XP) on their respective desktops and dock. It saves me a couple of steps and makes the rebooting process acceptable.
In Mac OS 10.5.2, navigate to /System/Library/PreferencePanes, and find StartupDisc.prefPane. Create an alias of the StartupDisc.prefPane, and drag the alias to the Desktop or the Dock. I changed the icon to a Windows icon, and the text to Shortcut to Win XP.
While in Windows XP, open the Control Panel, then right-click on the on the Boot Camp Control Panel item. Select Send to Deskto ...