To be honest? AC/DC; they've got plenty of good songs but plenty of duds as well. It's pretty much become one of those bands that if you ask someone, who's wearing their tshirt what their favourite song/album is, they either won't be able to give you an answer, or pick a really obvious one (most likely either Highway to Hell or Hell's Bells).
It's the same with Metallica and, to a lesser extent, Iron Maiden.