I've not modded my wii, but from reading and searching for the past few months it's really simple.
If you want to download the games, find them, download them, get the image, burn it using a number of programs (nero,imgburn). Stick inside wii and enjoy, well, enjoy if the chip has been installed correctly.
If you would prefer to skip the download part. You can do it one of two ways. One way is to get an LG drive and rip the game like a dvd. The other way is to use the SD gecko thing to download parts of the game one by one, then once the entire game is on your computer, join them together and burn it using one of the above mentioned programs.
Seriously, people are making these comments because it's been gone over a thousand times. A thousand times I know because I've probably read each and every one of them a few times. I'm just stuck because I'm on a mac and as far as I know, you have to have a windows machine and I sure as hell ain't putting windows on my mac.
Good luck, do some searching and try to burn a couple of discs.