Hmmm....there are alot.
I'll say Rocky. They cleverly brought that back in a sequel. So did Rambo and Die Hard.
Batman just had to restart lol. There was no coming back.
Casino Royale is my favorite movie of the bunch, so I went with Bond. The only other Bond movies I've seen in full are Goldeneye and Quantum of Solace, though, so I can't say whether Casino Royale was the biggest comeback.