Congrats on your puppies!
As has been already mentioned, two puppies are certainly not a bad thing and I do NOT reccomend seperating them or giving one up at this time. It's not impossible for you to train them, and it certainly is not impossible to raise two dogs. In fact, your two boys will grow together and have such a great bond - they'll keep one another company.
Your puppies are stopping on their leashes because they're still learning HOW to walk on a leash, outside, away from your home and their 'safe zone'. Like BenMax said, making the walks fun and high energy will encourage them to move forward, but don't get discouraged when they stop in mid-stride. That's normal puppy behavior, a matter of the puppy trying to 'control' his environment; and don't forget, they're still learning that YOU are the boss. By stopping, they are testing their boundaries - putting on the brakes and telling you that they don't want to go where you've asked them too.
It's important that you move through that, instead of allowing the puppy to sit there. Once your puppy has walked ahead for you, that would be a good time to turn around and go home. Never end the walk on a bad note, when your pup has stopped walking; but make these initial on-leash walks shorter (5-10 minutes) and gradually make them longer as they get older.
Do you have someone that can help you walk them right now? I ask because it might be easier during these inital stages, in order to prevent them from play-fighting while you're walking them. And remember - the reason they're play-fighting is because they've been given the opportunity. They're bored with whatever you're doing, and so they've looked to one another for entertainment, which is what pups are all about. Keep the pace brisk and call their names as you go - I like to 'WoooHoo!!" occasionally, which usually makes me look crazy but the doggies love it when you get loud and exciting.