Hi, good to see that you are curious about wii hacking. I've included a few points you might want to know about:
USB Loaders - these allow you to put games on your USB and play them on your wii. USB Loader GX is a popular USB Loader. Let be know if you want more info on this.
DVD Players - these homebrew apps allow you to use your wii as a DVD player. An example of these is WiiMC.
cIOSs - Custom IOSs are required to play some games which require a newer firmware. NEVER update your wii firmware through the settings, this will remove your softmod! Instead, if a game does not work, check whether a cIOS is needed and, if so, download it and install it by using a guide (see below)
Guides - WiiHacks has heaps of guides for games so if a game does not work try looking for a guide to make it work. The guide will usually tell you exactly what to do in a step-by-step procedure.
If you need any more info, feel free to let me know by posting here or sending me a private message.