<< And how much ram is adequate so I wont have to upgrade for a while. >>
Do you mean just the ram, or the rest of the system?
What are you looking to spend?
Here's what you should look for in a decent gaming system:
CPU: Athlon(Thunderbird) or Duron 700MHz and above is more than adequate. Your vid card will become the limiting factor in games way before the processor, plus the 700s overclock pretty well to the 900MHz area.
Memory: 128MB minimum. If you don't want to upgrade for a while then 256MB.
Video Card: Any GeForce 2 GTS, as people have mentioned the Ultra is a bit overpriced, but if you can afford it then g/a.
The rest will depend on your budget.