anything-30 is pretty much the wrong oil. like previous posters have said, there are a lot of write ups on here. to sum up the lower the first number (0, 5, 10...) the lower viscosity (thickness) at colder temps to lubricate the parts until the oil warms up.
bob's the oil guy has a great "course" called "Motor Oil 101" - it'll tell you everything and more you ever wanted to know about oils...
Motor Oil 101 - Bob is the Oil Guy
**also** go post pics of your black boxster on the
Official Black Boxster Thread