I had a look into how people with Mod Chips for their wii downloaded ISO files and how they managed to get them and play them on their wii.

This is basically how it is done. Firstly you need a membership site to give you access to all the files you need whether you are looking for games, movies, tv shows the membership site gives you access to all of these Once you have your membership and you have chosen your game all you need to do is click the download link.

Non membership sites are free sites that you can download games from however a lot of these files could contain viruses that is why I would always recommend a paid membership site as all the files are checked for viruses before they are listed Free membership sites might sound appealing because they are free but you just don't know what you are getting

Wee Downloader is the main site that I use as all the files are checked for viruses before they get listed on the site

When you have your downloaded game the format should be in ISO format. What you will now need to do is burn the game to disc. You can do this either via NTI , Nero or imgburn. With the Wii you will need DVD-R discs these discs provide the least amount of fails. If you are not burning to disc you can also use a hard drive to play the games on the wii by formatting the hard drive and plugging it into the Wii

You will need to Mod your wii to be able to play downloaded games. With your membership you will get all the software you need to set your Wii up to be able to play downloaded games

There is also no risk to your console. The games from the membership sites are checked for viruses before they are even uploaded to these sites. Once you pay for your membership you can rest assured that all you need to do is select which game you want to download. Download the game burn to disk, or transfer to your hard drive and then play the game in your wii.

Hope this short guide helps you with your Wii ISO Download