Hmm...okay. I just skipped over the 'modify any wii 4.2 & below' thread, but I must say that it doesn't install any programs you don't want or need.
Can you do it with less than in the guide? Technically...yes. But if you check these forums, you'll find that almost everyday, someone comes crying that their wii got bricked and that they don't have a means to restore things.
The problem is usually not due to these people being too dumb to mess with their wii, but because they followed a (often outdated) guide half-heartedly and didn't took caution until it was too late.
Let's see what the guide covers (a bit of an overview of the steps)
-safely update to 4.2. This is important because the 4.2 update removes all homebrew -> skip this part, and every disc update can be your last one (
recent example).
-bannerbomb: simply crucial to get started. No way around it
-the homebrew channel: while technically not required, it is HIGHLY advised. The reason: it makes the other steps and homebrewing about 100x easier. If nothing else, I suggest you try it until you're completely done with the guide. If you still want to remove it then, you can also do so easily (it's only 1 channel that takes up only a few blocks).
-DVDX: as mentioned, this can be skipped without problems
-bootmii: this program allows you to make full backups of your wii's hard drive. As with the homebrew channel, you don't HAVE to install it. And if all goes well, you'll never need it. The thing is...if something goes totally wrong, this proggie (and a backup made by it) is what you need to get things back the way they were.
-priiloader: while you may not NEED it (unless you're planning to use out-of-region games), it's still a good tool that'll prove it's worth easily. If you couldn't install bootmii as boot2 (depends on the model of your wii), it's just as crucial as bootmii itself.
-Multi-Mod Manager: not really crucial by itself, but it's purpose in the guide (restoring the trucha bug) is. So...just install it and follow the rest of the guide. You can uninstall MMM afterward if you have to.
Beyond that, it's a matter of how you want to play backups. Do you want to run them from an USB-drive or from discs? Either way, it'll mean installing even more stuff.
EDIT: 3 new posts since I made mine.
The zip is just to have all the mentioned programs in one bundle. All of those programs can be found individually by searching on this forum as well.
That "IOS thing" is most likely cioscorp (or darkcorp, which is the latest version of it). It basically patches everything under the hood (including trucha patching) to allow backup discs to be played through the disc channel.
In normal cases, that should be sufficient. But future proof-ness is always a bit tricky. Though darkcorp currently works great*, it's hard to predict whether it'll handle games like super mario galaxy 2 (which'll ship next month). Or a future firmware.
*note: keep in mind that the newer kinds of wii's have a different DVD-drive that simply can't use backup discs.