Depends on the game. Maybe make an extra user you can log into (fast user switching), where corners are disabled and play from there.
This isn't a problem of the computer or the OS, it's a problem with the game. Any good game disables all system-specific gestures and keyboard shortcuts to stop exactly this from happening.
Then do what has been recommended or contact the game developer, as it is not normal behaviour with properly programmed games that are in full screen.I have a mouse plugged in but it still happens anyway, playing mafia 2 so whenever theres quick cursor movements the screen starts bouncing around. into different spaces and mission control... v annoying.
Just disable hot corners. I'm using only gestures nowit happens no matter which game i'm playing, will obviously have to do more digging to get a resolution... thanks anyway