What breed is he?
There are many reasons why he could be barking at people. He could be scared, guarding, excited, aggressive, or just talkative. When he barks, watch him closely - does he back up while he barks (even just a tiny bit)? Is his body generally relatively relaxed, tail wagging? Does he jump on the people he barks at if given the chance? Does he growl a lot at people (besides you, besides in play sessions), or show his teeth?
Once you know why he's barking, then you can start to fix the problem. Meanwhile, though, you can work on making strangers more fun and rewarding for him - anytime he looks at a person (BEFORE he has a chance to bark), put a treat in front of his nose and let him have it (make sure it's a really high-value treat, like hotdogs, cheese, chicken, etc.). Or, if you're clicker training, you can click whenever he looks at a person, and then give him a treat. You do have to be really dilligent and quick, though, or you will accidently reward the barking.
For your other problem, it's probably a good idea to keep him on a leash while he's outside. You can just let him drag the leash, you don't have to hold it. That way, when it's time to go in you can just pick up the leash and encourage him to walk in with you. Nipping at your feet is probably a good time for a time out. And you can use the kennel - just very calmly (deep breaths!) pick him up (or pick up the leash) and take him to the crate. Leave him there for a few minutes (2-5 or so), and then calmly let him out. It will not make him afraid of the kennel or associate it with punishment as long as you stay calm and don't yell at him or anything while he's being "punished." Think of it more as a consequence - you nipped my feet, that causes you to be away from me for a few minutes.
