4 possible reasons:
1. You're putting it in the wrong way (non-illustrated side toward the majority of the wii)
2. You need a software update (should tell you when you try to play the game)
3. Your Wii has dust on it's reader and therefore can't read any games (test this)
4. The brawl disk is damaged in some way (scratched, chipped, etc.)
Try cleaning the disk. If that does not work, the drive in your Wii may be broken. You will have to call Nintendo Technical Support and have them tell you how to fix it or have them fix it.
Super Smash Bros., Super Smash Bros. Melee, Super Smash Bros. Brawl, Super Smash Bros. for Nintendo 3DS/ Super Smash Bros. for Wii U, Super Smash Bros. Ultimate.
You can only install Super Smash Bros. Brawl on your Wii with a Super Smash Bros. Brawl disc.
The "sequel" to Super Smash Bros. Brawl, in a way, is Super Smash Bros. for Nintendo 3DS/Super Smash Bros. for Wii U.
You can not get Blaze in Super Smash Bros. Brawl.
Super Smash Bros. Brawl happened in 2008.
No, in fact Shadow isn't even in Super Smash Bros. Brawl. He is from the Sonic games. Sonic however, isn't from Super Smash Bros. Brawl but Sonic is in Super Smash Bros. Brawl.
Super Smash Bros., Super Smash Bros. Melee, Super Smash Bros. Brawl, Super Smash Bros. for Nintendo 3DS/Super Smash Bros. for Wii U, and Super Smash Bros. Ultimate.
Sorry but no, Birdo is not in Super Smash Bros. Brawl.
No, there is no Super Smash Bros. Brawl DS.
Sadly, you can not be Rosilina in super smash bros brawl
Super Smash Bros. Brawl happened in 2008.
Super Smash Bros. Brawl.