I have been going to SFOG for a while now.
Definately must rides are:
Superman - if you can manage at least once in the front and then once in the back.
Acro - I would suggest starting on this one over DZ at PKI. DZ is higher and in my opinion a lot scarier.
Mindbender - My favorite coaster in the park. Classic Anton. A great ride.
Great Gasp - A classic ride that you should ride before they become extinct.
Georgia Scorcher - great standup definately worth a trip
Batman - if you fell like waiting...would suggest waiting til around close to ride this one.
GA Cycl