Eh, Masterchief is a good choice too actually, though i kinda disagree. Even with the massive marketing blitz's and "Master Chief Banks here" stuff i don't think most people know who he is, i don't think he penetrated the market much beyond the gamer market. I think everyone took notice then put it out of mind.
I think if you showed a picture of Master Chief to people most non-gamers would have no clue. While more people would get Lara Croft. I blame it on Master Cheif not having a face... or a movie. While Lara has both.
Of course Lara Croft doesn't sell well anymore but i blame that more on the quality of the games. I mean the Lara Croft games are what got my Aunt into gaming. She'd heard of her before, so she bought it for her computer cheap... got addicted and bought a 360.