yes i hacked my wii about 2 years ago and it's great. i also hacked my ds lite, but thats another story.
ill answer any of your questions, i know pretty much all there is. im not trying to sound cocky but i spent days, if not weeks, learning everything.
if you get the homebrew channel, which is so easy with the 4.0 update, you can do so much more. you dont need a wiikey, no hardware, just patience and you're set. you can download and play ANY virtual console or wiiware game, for free... you can play all the fun homebrew games, use the cool homebrew utilities, etc. also, if you use Ocarina, you can use some pretty nifty cheats in real wii games. you can also be able to play full wii games, but im not 100% sure if you need a wiikey or not. i think you just burn it as a ISO file, then use dvdx. but whatever.
anyways, look, i would really suggest it. it's so rare for your wii to brick. you just need to make sure you dont install sketchy wads if you wanna play wads. wads are vc and wiiware games btw.
id suggest visiting wiiso, its super legit. and wiibrew! both are key to life. youtube also has some dece tutorials. if you want help, post here or pm me.
just to add, softmii is an app that enables you to change the wii home menu theme, its rad.