What legal measures can I take to make sure this doesn't happen again?

I have to wonder what you did or said to deserve this.

Do I personally have to pay back on a contract I signed for personally and signed for on behalf of my business after a chap 13

Yes. You and your business are both separately on the hook if you reaffirmed the contract after filing the 13.

If it is illegal to let cats roam in your city, report this to Animal Control.

Can I file a case against Dallas airport or American air line

An unexpected mechanical problem with the elevator is not a cause of action against the airport nor the airline.

Child pornography is illegal to produce, distribute, and possess.

Are email advertisers/marketers REQUIRED to obtain explicit/ express consent in order to email you?

I get my email via Gmail.com, which knocks out nearly all spam.

Can I file a claim against a city municipality for deprivation of rights?

Free parking is not a human right. . .

Am I liable for injuries caused to my neighbors dog by my dog even though both dogs were off leash and in the street?

Yes. Pay their vet bill, and control your dog.

I'm 23. I called a 15 year-old sexy just to be silly in the context of the conversation. Did I break the law in Ohio?

No, but almost. . .

Can I get out of a contract of selling my house, one month before closing?

Ask the buyer if they will agree to cancel or delay. Easiest way. They may be having second thoughts too. You might owe the agent his commission.