Caddy seems like the safest pick. Gotta put my money there.
For a sleeper, I'll pick Alex Smith. I think he could have a nice career ahead of him. He's very bright, and has good skills to boot. I think he could adapt fairly quickly as the season goes on.
I'm in Chicago and clealry Orton deserved to start over the other trash that Chicago has been trying to pass off as QB's. That said, I think his going from 3rd string to starter is a pretty big leap, and he may not be so well prepared.