Not quite sure what your asking. Are you asking how to extract files? How to upload a torrent? How to burn the game?
If your asking what steps you would have to do in order to burn the game, then ImgBurn is fine to use. You have to make sure that you use DVD -Rs [not +Rs]. If you have Imgburn installed, then all you need to do is right click on the ISO file you have downloaded, and choose to "burn with Imgburn". Then, once it's done burning, you need to have a Backup Loader installed on your Wii [such as NeoGamma r7/8] and your good to go.
On a small note, if your trying to play an out of region game, then you must force the video to your region [this can be done in the setting of the backup loader]. So if your in the US [NTSC] trying to play a european [PAL] then you must force the video to NTSC.