For a long while now I haven't been following the homebrew scene with my Wii. Things seem to have changed a far bit since I (mostly) stopped playing with my Wii, and I never really understood things back then anyway.
A friend of mine just won a Wii in a competition he didn't enter and is interested in joining me in the homebrew scene; and so, long story short, I want to get back in.

If you would be so kind, I would like a little help cleaning up my Wii before I start again. I want to wipe all traces of homebrew apps and mods from my Wii and start afresh.
Some programs I have already deleted myself, being self explanatory (various little apps from the Homebrew browser), but some confuse me. I'm unsure how to properly remove them and all tracers from the Wii's flash drive/firmware.

Some quick background info on my Wii:
Serial number is LAH100183108
Model number RVL-001AUS
Firmware version is 4.0E, I think it has been patched with hack IOS's
Homebrew channel was first installed with the twilight hack, then reinstalled with the BannerBomb hack. The Twilight save has since been deleted.

What I have installed, and would like to completely remove...

System Menu:
When I boot the Wii I get the BootMii startup menu (which I hate)
Backup launcher on the system menu
GC Launcher on the system menu
Wii Homebrew 1.0.1

In the Homebrew Channel:
Gecko 1.8
Homebrew browser

And the things that seem to only appear on the SD card:
WAD Manager 1.3
cIOS249 rev9
IOS35-64 v1040
Neo Gamma R7
totally forgotten what this is.

What I intend to do with my Wii after:
Upgrade to firmware version 4.1E
Reinstall Wii Homebrew Channel
Install USB Backup Loader
Install BootMii as boot 2
I would like the ability to launch GC backups
I would like the ability to launch my American imported SSBB
I would like to retain my save files, virtual console games and channels.

Most of this will no doubt be a quick and simple delete, I just want to make sure I am wiping clean any residue so to say.
I hope this isn't too much of an ask but the Homebrew scene and modding of the Wii is incredibly confusing at the best of times.

...and two final and optional questions:
When I try to access the SD card menu form the system menu the Wii locks, what does this and has it been fixed?
What is DVDX and what does it do?