The Best Option For You Is A Wii Softmod

Pros

-The ability to backup your games and play them from a USB device.

-Turn your Wii in a Media Center (Play Movies, Music and more from USB, SD or DVD*)

-The ability to play games from other regions (full region free)

-The ability to use dozens of Homebrew Applications

-Custom themes for the System menu.

-The ability to move your disc channel.

-Use emulators to play various games from the past.

-Play game hacks, such as the Brawl mods and texture hacks.

Cons

-None that we can think of

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* DVDs will only work on older Wiis. On more recent Wiis, you can only use SD and/or USB.