Nothing working at all (MAC)

So im super desperate to get in and play some wrath content but after i downloaded it (for mac) i don't have wow.exe just "world of warcraft" (68.1 MB) and "world of warcraft launcher" (6.5 MB) both of them just say the application can't be opened. Also, when i go to change the realmlist it just says that it can't be opened because i don't have a program to open it. I'm not sure what program I'm missing though? if anyone could help that'd be much appreciated. sorry if i left out anything important, I'm not super computer savvy...