ok, a couple of points for noobs to this game:
you get point for how many people get infected and how many die. These points show up in the "Virus" screen (the squiggly line looking thing at the bottom right next to "Go" button). All the checked and unchecked boxes you can alter to your pleasing, as long as you have the required points. Press back then return to the virus screen after pressing go to see how many points you got from the round.
I usually press go between 5-10 rounds each time in order to get enough points to do something with. Remember that the more deadly your virus is, the quicker the countries will be to close their borders. As a result, create a low fatality, but highly contagious virus so it spreads, then add all the deadly qualities you can with the points you;ve amassed by waiting for the viri to spread. this is by no means the ONLY way to do it...you can do it anyway that works for you.
there ya go, enjoy the game.