What's your current situation?
Time required: 20-30 minutes.
NOTICE: This procedure is safe, but random power outages during key points of installation or failure to correctly follow the instructions may lead to your Wii breaking. As such, we hold no responsibility for such occurences.
Also, installing software not approved by Nintendo on your console renders your warranty completely void!
If you're worried, the "I don't want to install anything" option is the safest method, and will make no permanent modifications to your console - once you turn it off, it will go back to the way it was before you ran any homebrew software. There is very little risk in following this method!