~~No you will not go to jail. What banks do is enter you into the CHEX system and you will not be able to get a checking account until that money is paid back.
In the meantime they will enforce collection proceedings against you, which will cost you more money after they attach their fees, then take you to small claims court. Once there you will both present your sides and a judge will decide (without a doubt on this the judge will grant the bank a judgment against you). Then they are able to attach your bank account, lien any property you own that could be sold to satisfy the debt, or garnish your wages, basically whatever means they can to get the money you owe them.
As for the last part of your question, even though everyone is very mad about what the banks have done to cause the financial downfall of the economy, two wrongs do not make a right. When you owe money, it must be paid.~~