The Wii I'm using is 3.4. They've made a work around that won't brick your Wii. And you can't do what you say you want to do with Homebrew, anyway. You can't make mountains and stuff... I'm pretty certain you can't even change your town layout at all. But anyway...DON'T DO IT. Hacking is a no no. (I'm not hacking my town... It's just a temporary one on my friend's Wii until I get mine back.)
You obviously dont know what you are talking about. Homebrew does not brick Wiis unless you do something really in depth like install a different region's firmware or an incorrect softmod. Nobody has reported bricked Wii's from installing homebrew, and the most harm you can do by hacking Animal Crossing is do too much to your town which will cause the save file to corrupt. Although I do think you cannot install it ATM.
I use Homebrew to make backups of my town, play games that people make and other very useful tools. Installing the homebrew channel does not make you a hacker, there are many things it can be used for like playing DVDs, listening to music, etc. You choose whether you want to use it as an enhancer or a hacking program.