Dell financial services False payment recording, Sent faulty computer, Continuing Charges exceed Cost and failure to fix computer under warranty Internet

In 2007 I purchased a desktop computer under a special advertised sale with Dell. they failed to fix the faulty computer under warranty and redirected me constantly for one year until it ran out and have now continued to bill and charge me 2600.00 or original purchase of 1300. even though i was paying properly on the bills. they have phone harrased me in the past year during some emergency events and all day long 24/7 during work. They refuse to respond originally to a report to their highest peers to fix the computer when needed to use during a military deployment in my family. i need to recoupe my money, fix and clean off the computer of secure and important files and sell it to help pay off the balance actually due not the amount going up now each month with illegal excess charges of late fees and interest of over 29%. they are crooks! and fail to help their consumers.