I'm actually fairly impressed. I've broken/scratched CD's on purpose before, and it's actually not very easy to do. Especially with nothing but teeth!

I do.

IF I remember right, the Homebrew guys are pretty anti-piracy (officially). I'm pretty sure you need the Homebrew channel, and then another application loader on top of that.

Slim, but non-zero. If you do your reading, it's not something I'd worry about overmuch, especially since a Wii can be replaced pretty easily.

In my opinion, playing backups (or "backups" using Homebrew is not worth it. It took me an hour or two to get it working, and even then I was not satisfied with the performance. I'd get frequent freezes and such when using the loaders, and when I could get the backups working, I'd have weird gameplay issues. I have no idea if the problems were my fault or if they were inherent to the software. Perhaps things have improved in the past year or so since I messed with it. Anyway, you're obviously welcome to mess with it if you want, and it's probably not very risky, but I didn't have a very good experience.

As an alternative, you might try the Dolphin emulator for your PC. If you have a fairly modern computer, you should be able to play Wind Waker at full speed with very few visual glitches. Dolphin has come a long way.