Overall the selections at the place are pretty bad, while the quality may be good choices are quite limited.
To get it lower you'll probably have to go with a lower end graphics card, but this one would play real nice at 1920x1080.
You know, when upgrading, changing the CPU is very complicated and time consuming when compared to simply changing the videocard. A lot of screws, thermal paste...cooler etc..therefore....
Get the i5, you wont regreat it going quad-core. Use intel graphics for a 1 month or 2, and later on add in a video card, this will give you time to get some money, maybe a few extra hours at work? Or simply beg for 2 dollars on the street everyday, after 2 months you get a $120 videocard.