There's usually a pre game rally at the Sproul Steps where the band and the cheerleaders perform if you have some time to kill. It's about 1.5 hours prior to game time. My wife likes to go, although maybe you might find it weird to go to the opposing teams rally, lol.
Fat slice, top dog, etc are popular with the students as bcla mentioned, at least the ones that my wife/friends talk about who went to Cal. The last time we went to Berkeley we went to Uji Time Dessert, which is sort of a Asian inspired soft serve place if you're into that sort of thing. I had the black sesame soft serve parfait which was pretty good:
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(Picture stolen from Yelp, but it's the same thing i had). That fish thing is called a taiyaki. It's dough with a filling (usually red bean, Nutella, chocolate, or other sweet filling)
I've never been to Fat Slice, but top dog was pretty good. They have a variety of dogs / sausages you can order.
My wife also likes this place called Barneys, which is a burger joint, though I think it's more of a nostalgia thing rather than the food at this point.
Not sure about the parking situation, but if you're going to try to park there I would go really really early.