preloader is a small application which places itself before the system menu.
It's main feature is to directly boot the Homebrew Channel or a file you can install from a FAT device.
preloader is also able to apply memory patches the system menu to remove limitations or other things.
Since preloader places itself before the system menu any problems that would cause the system menu to fail are not causing your whole wii to stop working.
If autoboot is enabled and you want to access preloader's menu simply hold RESET while powering the wii on.
0.29:
-added a feature to load the system menu with any IOS version you want.
-The installer includes an IOS patcher which when found patches IOS60 so preloader can fully work with system menu 4.0
-Moved some text around for better visibility on 4:3 screens
-fixed a bug which let the disc endlessly spin when wc24 was enabled and the wii got turned off
-fixed a bug which broke system menu loading when the system got formated