Don't worry about EmuNAND. If really needed and requested, I could write something myself.
Anyway, thank you for your future help in the wiiU part of the wiki !
I started it but it's missing so much information right now, all homebrew individual pages are missing. I have an idea for another page too, but don't know how to write it and which layout to use yet. I might talk about it with you.
I've read through several forums trying to understand it all but I always catch a snag when I come across terms like NAND and IOS and the slots they're installed or whatever. Several guides I've read also highlight the fact that you should know what you're doing before attempting any hacking, but I can't find anything to give me the information I need.
That's what I don't like about tutorials. They don't explain anything and only tell users which button to press blindly.
when I write guides and tuto, I prefer explaining things and why users have to do that, how things work, etc.
Not everyone has the will (or even the knowledge) to do that. most guides are written by "noobs" who succesfully hacked their console following a youtube guide and create yet another fail youtube guide, without taking in account new hacks, user's differences, etc. and it could be dangerous to follow them.
This guide has a looot of details, even though it might not explain all the terms and how the console's internal work.
the console doesn't have a firmware, but a set of different "drivers".
Everything that runs on the console (being system menu, game, or even homebrew) uses a specific "set of functions" called IOS (Input/Output System, the drivers if you want to compare them to computers) responsible for the hardware communication between the program and the console.
Instead of updating a single firmware, nintendo decided to keep different version of these IOS for old games, and release new IOS for newer games. for example, a game which require USB2 access will use IOS 58, while Zelda twilight princess will always use IOS 9 which is very old, but it's working like that to ensure compatibility and bug free updates.
So, the Wii (and vWii), have these different "IOS" version stored in different sub-folders of the internal memory.
The Wii can select up to 257 different folders, that what people are calling a "slot".
Slot 9 = folder named "000000009" which contains a pack of functions a game or any application can use to communicate with the hardware (wiimote, disc, internal memory drive, usb, etc.)
Nintendo released a lot of IOS version, some for the games, some for the different system menu versions. Up to "slot 80" are used officially by nintendo.
Hacker are editing these existing files and installing the result in another empty folder, by convention it was decided to install them on folders numbered 200 and higher.
The USBLoaders are, for example, usually loading the IOS installed in the folder (slot) number 249.
You should often see something like this :
IOS249 [56]
which means that the IOS installed in slot 249 contains patched IOS files based on the official IOS files of nintendo located in slot 56.
the "drivers" in slot 56 are patched to add hacking features (redirect disc access to USB, patch the signature check, etc.) and the result is installed in slot 249, keeping the original slot 56 untouched and available for official softwares from nintendo.
The internal memory of the Wii is not a hard drive, but a flash-memory chipset type called "NAND". Since the Wii, a lot of people are calling other console's internal memory a NAND while it's not necessarily the same type of chipset (NOR, NAND, eMMC, etc.)
You might often see the term "emuNAND" too, which is a deformation of language, it's not emulating a NAND chipset, but redirecting access of the NAND to a copy of it.
Users are making copy of the internal chipset memory (the console's data) to SD card or USB, and the console is reading the data located there instead of the one located on the real chipset.
It's redirecting the access to a copy of the memory, allowing users to mess with the copy, install games and do dangerous things on it (like changing the system menu theme, picture, sounds, etc.), if anything goes wrong, the real memory is still good and unaffected ! You might also encounter the term "redNAND" which stands for Redirected-NAND.
Sorry, I like to be descriptive too ! haha
Is it possible to use my 32GB flashdrive, which is formatted to work with my system and holds a bit of save data for one of my WiiU games, to run Wii ISOs?
No. You can't use a WiiU formated drive for anything else. The WiiU deletes all partition information and you can share the drive with another device or application.
All emulators, ROMs, and save data for those ROMs, as well as homebrew apps, are stored on the SD card, right?
Yes, you can store them on SD, or even USB ! as long as it's formated to FAT32 it can be accessed by the homebrew channel.
Some homebrew are even compatible with other formats, like NTFS, ext2/3/4 or exFAT.
Is it possible to enable DVD and CD playback on the Wii U using vWii?
No, the drive is physically limited and can't read CD or DVD. it can't be fixed or updated.
I read that it was possible back in the Wii hacking days using MPlayer, but compatibility was broken. I also read that there was a rumor that it slowly damaged the laser. If it's possible, would that be true?
It worked on older consoles. Nintendo updated the drives on newer console and you can't read CD/DVD/DVD-R on newer drives.
I don't think it damaged the lens or laser, the laser itself just emit light. if the lens is damaged it's probably due to natural electronic device wearness.