I installed it as part of a hacked menu but I have 'Installed File' and 'Load/Install File' and don't kow what they're for. I really want to familiarise myself with everything homebrew related. There doesn't appear to be a n00b guide section!
Load/install file is so that you can setup a program to run from within preloader then 'installed file' is to run it.
Do yourself a favor and upgrade to priiloader (a continuation of preloader from another author since preloader is now well over a year out of date) as it's more stable and supports a few more features.
The problem is, priiloader will not save you from 90% of the problems you can cause to your wii. The only things it can really protect you from are....
A: A bad installed theme
B: A banner brick (a malformed banner in a custom channel or a corrupted banner in any channel)
The majority of bricks that people do tend to be IOS related (deleting random IOS because a guide told them to, upgrading their system menu IOS to a stub since they use an older system menu, etc etc) which priiloader won't save you from (since, last I checked, it runs off the same IOS as system menu)