Help me play a mod- I can't figure this out

[bsem]

Hi all. Someone please help me. I've downloaded a few mods (Wrestlemania 24, which I extracted but can't figure out how to play AND Legends 2.0 which I can't even extract). I do not understand how to play mods. I have a Mac w an intel processor; I have a regular No Mercy ROM that works fine and I have a Sixtyforce emulator. I just don't know what to do once I download a game. I will download whichever games are easy to play. I just need specific guidance cuz I don't understand the jargon or how to get the game going.

Thanks all.