so i see you are new here. Welcome to Tech-Forums.net!
well, where to get started. have you picked out the main parts of your system yet? motherboard, cpu, case? if not we can help you, about 15 of us here, we just hear the phrase "help me with a build" and we pounce on it like cats on mice.
well anyways, past that. I suggest
this but this is way above your price range, the percect fit would be a 20.1 inch widescreen
this which costs roughly 210 us dollars.
for a graphics solution, i would suggest a 7600GS, its a little on the expensive side, but it has great potentail,
this, or
this would work perfect.