Savage Worlds: World of the Dead (+ maybe Accursed)
I just recently received the World of the Dead supplement for Savage Worlds. Since I haven't really ever played SW and would like an intro to it, and love zombie apocalypse games, an Adult WotD game would be fun. I also received Accursed along with it, so if you want to use options from that game, too (mixing supernatural elements with a zombie apocalypse scenario) I'd be down with that.