Dop-Mii is used to download and install IOS's and can also patch most IOS's if you wish. You can also use it to run a system check on your Wii, which will report which IOS you have installed and whether or not they are patched. It will save this info to an excel file if you wish.
I'm not all that famillar with Gecko, but for people to help you, you might want to list some info about your Wii. Like what systemenu you are using and which CIOS's if any are installed. As well as if you are trying to run backups of disk or off of a usb HDD.