Go to HP.com and look for a machine. You obviously don't know anyone who can build a machine.
If you want a machine built, then get a AM2 socket CPU AMD, motherboard with onboard video, LAN card and sound, Abit has a nice motherboard. 2G on the CPU is just find. Get a GeForce 5200 or above. Get a SATA Drive (new standard) Monitors are hard, you need to go to a computer store and review some LCD monitors, what can you look at without hurting your eyes. You should be paying around $300 for a 20" LCD. You should go with a 500 watt power supply.
Oh forget Dell please.