Hi young people! We are not miracle workers here on the HP forum. I know you are upset because your PC stopped working, but we can't just snap our fingers and fix your problems. Please familiarize yourself with this. Then post back with what you tried.http://h30434.www3.hp.com/t5/Desktop-Operating-Systems-Software-Recovery/OS-Recovery-HP-Recovery-Manager/td-p/2235683
You used a damp cloth to clean?????. Computers and water don't mix. You need to research these things. You clean a computer with compressed air. You need to have a anti-static wrist band to stop static electrical damage. There is no telling how much damage you have done to your PC.
Dokie!