Unfortunately the only Mac version of Sims 2 is the Super Collection from the App store, which doesn't have all the packs. I'm not sure why, but EA never had Aspyr finish porting the game over for Mac. I've always played either on a Windows machine or Windows partition on my Mac. If you don't like the idea of getting a second Windows computer, I suggest looking into Parallels. It sets up a partition on your machine to run Windows.
If they ever made Legacy run on a Mac, I'd get rid of my second machine in a heartbeat. I'm not a fan of Windows.
