How can I set my bootloader to load my primary (C:) partition?

How can I set my bootloader to load my primary (C:) partition?

I created 4 partitions and want to use them to have seperate Windows XP, Windows 7, (possibly) Windows Vista installations, and "WinDummy" (to test applications in Vista, XP or another OS). I used Norton Ghost to install an OS to the drive in about 3 minutes.