The Black Wii's and Wii's with a serial number around LEH278xxxxxxxxx have a new DVD drive installed which will not read standard blank DVD disks, to read normal blank disks a drive swap is required. Normally customers use the external hard disk feature of the softmod if this is the case.
The Homebrew Channel allows you to run Homebrew applications and games
The USB Loader Channel allows you copy your original games directly to an External Hard disk or SD Card and play them directly from that device. So you can copy all off your games to an external hard disk and never have to insert a DVD again.
**** Note ****
To use the USB Loader channel, you will need to download the files HERE, unzip them to an SD Card and install the card into the front of your Wii. The files you are downloading are configuration files.
All we need is your console (without any leads or controllers, etc), then our engineers can make the changes required to fully open up your Wii.