GPA. As mentioned above, your GPA is only necessary if you are a recent college graduate and do not have work experience to back you up. There are a few jobs that require a GPA, however, including engineering and finance.
If you have major gaps in employment, there are a few ways to make them less noticeable like a change of resume foramt. It is important to be honest about gaps in your resume and not try to cover them up, but to also make them seem productive and intentional. Adding volunteer work or classes in the time you were unemployed is highly valuable and fairly simple to get starter with.