You can eliminate all debts that are dischargeable. Examples of dischargeable debts include: credit card debt, medical debt, repossessions, foreclosures, personal loans, etc.
Debts that are generally not dischargeable include: student loans, certain taxes, child support, alimony and debts related to criminal activity.
As of today, all accounts must be included. If the debt is a secured debt, such as a home or a car, you can attempt to reaffirm the debt. Unsecured debts must be included and will be discharged.
If you receive a discharge for a Chapter 7, you must wait 8 years in between filings. If you received a discharge in Chapter 13, the timelines depend on which chapter you need to file now.