First, I'd like to welcome you to the foums and congradulate you for making such a detailed help topic, since too many n00bs post just things like helphelphelp. Like they want to help me, not vice versa.
Okay, it's obvious that your PC is waaaaay too fast for SA. The problem is probably that your frame rate limiter is turned off. So just go to options>video and turn the frame limiter on. This should lock your frame rate to 25fps and make the game playable to average people, not only some ultra-mutants with 1ms response time. And of course, max the details.
Btw some killing specs you've got there. Can I have your computer for a bit?