If you boot multiple operating systems from a single Windows Vista/ 7 PC then it's important to master your Windows Boot Configuration (BCD) store, the technology that manages this data. Windows has a command line tool to help, but your life will be much easier if you download and install EasyBCD - it provides a straightforward GUI and all the boot management options you'll ever need.
You're able to view the boot menu settings, for instance, and then edit them. Options include the ability to reorder the menu entries, change the default, set the delay before the default boot option is selected, or perhaps skip the boot menu altogether.
Windows experts can manually tweak more advanced settings for particular Windows installations. You're able to choose the default PAE or DEP behaviour from a list, for instance. And if you're annoyed by 64-bit Windows' insistence on installing signed drivers only, then you can turn that behaviour off here with a click.
EasyBCD really comes into its own if you add a new boot menu entry, though. It's extremely versatile, allowing you to boot into everything from DOS 6.x or Windows 95+, to Linux/ BSD, Mac OS X and more. And it can boot operating systems from ISO images, Windows 7 VHD images, Windows PE WIM images, as well as network drives, CDs or USB flash drives, even if your PCs BIOS doesn't support it normally.
And useful management tools include the ability to back up and restore your BCD data, handy if they become corrupted. If your PC isn't booting normally then EasyBCD can also repair your boot files and quickly restore normal operations.