those tires should do pretty well in the sand actually, big aggressive mud terrains dig in way too much. Just air them down to around 12psi and take it easy, and you shouldn't have a problem.
As far as an easy route to the beach, just keep going straight (West) after you leave the woods on the entrance. After you get past Test hill (the big hill on the left), start to head a little bit to the left (south). Keep heading in that direction and after a small hill, you will see the big flat area between the two bigger dunes that gets used for drag racing a lot, just watch where you are going because you don't want to cruise out in front of people who are in mid-race. Follow that gully/flat area straight out to the beach and you are all set.