The Vital Records office is not a very useful Pennsylvania background check resource unless you are trying to research a family member. They only maintain birth and death records, which are tightly restricted to relatives only. If you want someone's marriage history, you may be able to request related documents from the county courthouse in the county where the marriage or divorce took place.
A much better Pennsylvania background check resource is the Pennsylvania Access to Criminal History (better known as PATCH). Their website allows the general public to make criminal history searches on anyone, at a cost of $10 each, which is paid by credit card and is non-refundable. Some employers may be able to use the system at no cost if they are regularly screening employees and applicants. Results of "no record" are returned immediately but others may take more than a week to be sent back to you.