To find out how to get the homebrew channel on 4.2, click here.
Since you have a 4.2 Wii, you can’t do some things like, for example:
- Loading ISOS (games) from DVD-R discs
- Loading ISOS (games) from USB/HDD/SD storage devices
- Watching DVD movies
- Installing WAD’s
- ..and other things
So for this reason, some tutorials on this site will NOT work for you. In order to have the maximum homebrew compatibility with your 4.2 Wii, first you must restore the trucha bug (click the link for a tutorial).