My undergrad gpa is less than stellar. It sits at a 2.7 cumulative. I'm trying to decide if I should return.?

My last semester there was my worst; I even receive a F. Currently, I just have to take 2 summer classes and I'm done. These classes will be taken at a different school. Because of the school's later schedule, I won't receive my diploma until December. So I'm considering a return for the fall semester to beef up my gpa and retake the F class. Basically my question is should I return or should I just let it go and move on to post bac? I'd like to go to grad school.