No idea what "video9" is that you mention, but anyway:
Provided your Wii is currently running the latest version of the System Menu (v4.3), all you should need to do is install HBC (follow the guide here: [
wiisixtyfour.webs.com]) and then run WiiMC from there (there are some pointers regarding that to be found here: [
wiisixtyfour.webs.com]). If you want to have a seperate channel for WiiMC instead of loading HBC first each time, download the WiiMC channel installer from here: [
www.wiimc.org] and run it from HBC (you need to have WiiMC setup on your SD card the same way as if you were going to run it from HBC, or the channel won't work, so make sure you can run WiiMC from HBC before installing the channel).
If your Wii is
not on the latest update, the easiest thing to do is update it (just a regular update from the Settings menu) and then install HBC and run WiiMC.
The talk of IOS is because the Wii has pieces of software called "IOS" (Input Output System) which are essentially the "background" code that runs at all times. Stuff like the System Menu and games will tell IOS that they want to access certain pieces of hardware, and IOS will then allow them to do so. It's important for WiiMC because most versions of IOS can only access the Wii's USB ports with a 1.1 access speed, but IOS58 has support for USB2.0, so obviously it is preferred. Every Wii contains around 20-30 versions of IOS, some with different features. IOS58 is the one used for homebrew due to it's USB2.0 support.
You don't need to worry about this really, other than to know that if your Wii is fully updated, it will have IOS58 and so USB2.0 will work in apps like WiiMC.