There are a number of tires that will work on the Honda S2000 but the three or four best that I have seen are the Bridgestone Potenza RE-11, Dunlop Direzza Star Spec , Yokohama Advan Neova and the Kumho Ecsta XS . All of these tires are going to give you excellent performance on the street and can be driven in an autocross or on the track. They are suited for someone that is a very aggressive driver that really wants the best performance for his or her car.
The tire that I would have to rank as the overall best would be the RE11. In testing they held up the best and offered the best wet traction.
If you are looking for the extremes you cannot go wrong with any of these for the S2K. Great for the street or track.