The best way to un-jailbreak an iPad is to (1) connect it to iTunes, (2) make a backup and then (3) select the Upgrade or Restore button.
iTunes will do its magic and, on prompting from iTunes, you'll put the fresh backup on the iPad during the upgrade process.
Once iTunes is finished, you'll have an iPad 2 running iOS 7.0.4, stock.
Good luck and let us know how you get on.
Marilyn
P.S. And, since you talk about a jail broken iPad, I've taken the liberty of moving your post over to the Hacking section. Thanks for your understanding.