The Chapter 7 discharged your debt (as long as you did not sign a reaffirmation agreement) but it did not discharge the mortgage. That means the...

I want to file for bankruptcy ... and keep my house ... is it possible ?

Based on the information in your question, you will be able to file bankruptcy and claim your home as exempt. By claiming the home as exempt, you...

A debt collection agency is demanding payment in full on an account I don't recall ever owning, and threatening me

Whatever you do, do not give them your bank account information. According the Fair Debt Collection Practices Act they are required to send you a...