So is this a new Wii? Check the serial number against this list Wii Drive Chip Database
You don't need Wiiconnect24 to use Bannerbomb. It's quite clear that formatting your Wii was a very silly thing to do. I'm still not sure why people think this is a good idea, other than to mess things up and remove your game saves.
I wouldn't recommend doing a NAND restore with bootmii/IOS unless you want one of these..
Run signcheck http://wiibrew.org/wiki/SignCheck, press reset a bunch of times and post the resultant signcheck.csv text from your SD card.