Yes, a smaller size would do it. However, the Newegg calculator isn't that great, and the 750W allows for Crossfiring in the future, as well as overclocking everything, adding additional components and the inevitable aging of the unit.
If you don't want any of that, I can give you a revised build that will either be cheaper or have a bigger GPU, depending on prices.
Not even close. You'd need an HD 5870 ($400ish) to do that.
It would be able to handle it at 1600x resolutions though. Anything above that and you'll need a lot more cash. The 5850 ($300) handles most games at 1900x (major exception is Crysis). The 5870 can handle everything at max settings at maximum resolutions.
hes right either for the processor a core i5 or the x4.
Cores an overkill unless you plan on doing it at 1080p+ resolutions.
5770 is not better than a gtx260 but its dx11.
I would recommend 4870 coz its in the same price range.
If you can get the gtx250 core 216 its good but i doubt it will be in this price range..if you can save some from these...
Corsair TX750 or HX620 or VX550 are more than enough for : gtx 260, 4890,4870,5770,5830.
IF you want to play high end at DX11, then get any card in 5800 series like 5830,5870 etc.
You could save some money on the motherboard if you dont plan on going for sli and crossfire....
The 4870 is more powerful as a single card, but it runs hotter and uses more power. The 5770 is more powerful once you add a second card in Crossfire (compared to 2x 4870s) and has additional features such as bitstreaming and Eyefinity support.