I am just about to start out with flight simulation and am torn between FS 2004 and FSX because I am not sure if my pc setup is really good enough for fsx. My pc does pass the minimum spec for FSX but I wonder before I start to purchase either plus software whether someone could advise me further.

PC is Pentium Dual Core E6500 2.93GHz, M/B is a Gigabyte P43-ES3G, 4GB ram (3.25 according to system), NVIDIA Geforce GT220 (I am prepared to upgrade the video card a little if need be but pc is only a few months old), 445GB free space on hard drive (90%) NTFS.
Any advice welcomed, before I part with some hard earned cash, thanks.

Thanks for prompt reply and will go down the FS2004 route, a lot cheaper. Can you suggest any 'you really do need'  add ons like maybe acceleration, IR and training software / books as I am a complete beginner. I was also considering the Speedlink Black Widow flight stick. Can you fly 2004 virtual on the VATSIM network? Advice welcomed please. Thanks