[Scuderia_Turini]

Hello Ninco2000,
I will sort out pictures of the track installation but meanwhile lets confirm what your computer has.

In the photo below (showing the rear of a computer), the connector in the red area is a Parallel port, some times known as a Printer Port. These are normally as shown with 25 small sockets.  A 25-way Serial Port has 25 pins.  (Apologies if you already know this stuff).  
You would need a "25-way D-type" connector with pins to plug in.


The two 9-pin connectors in the blue area are Serial Ports. You would need a "9-way D-Type" connector with 9 sockets to connect to one of these.  

Obviously you will need suitable cable to connect up with, preferably the type with a metal mesh shielding around it to reduce the risk of interference from the car motors.

Other questions:
Where in the world are you? I am in the UK.
What version Windows does your computer operate on?
How far from the track will the computer be?

Leo