Is it possible to 'refresh' a game?

[Derpstorm]

To make a long story short, I was playing Brawl, and I got bored. So I used a cheat to build up damage on the sandbag, and then falcon punched it over 9000 feet. While using a crappy recording program. When I next started up the game, the emulation speed was 0 or 1% with a black screen and no audio. I tried a few things to get it to work, to no avail. What I want to do is sort of 'refresh' my game, so it's as if it's my first time starting the game up. It wouldn't be much of a loss, since I can use cheats to unlock everything that I had unlocked. The problem is, I don't know how. I have tried various things, *coughdeletingstuffcough* including re-installing Dolphin, and nothing has the desired result. All I want to know is what to delete, or if it is even possible. Any help would be appreciated.