http://pcpartpicker.com/p/rnco
$370 - 20mail in = 350
This is a cheap AMD trinity build with A4-5300, 1tb hd, dvd burner, micro atx mobo, corsair 80+ 430w PSU, 2x 2gb cas 8 ddr3 1600 ram, win 8 64bit oem (can swap for 7 if you like)
A dual core build should be more than suffient for your needs, I don't see much point in going with anything more. For rest of the parts it was high quality parts I can get for cheapest price kind of mentality, though the HD was because the price difference for any lower capacity to the 1tb wasn't much.
Went with the win8 OS due to improvements in boot up time and some other areas. And most people who I know actually used win8 don't hate it as much as the people who haven't who seem to dislike it the most, though the OS does have it faults no denying that, your call on the OS.
Didn't bother trying to squeeze in a SSD as much as I like due to budget constraints with having to include OS as I would have to upgrade mobo to something that supports 6gb sata to take full advantage of a good SSD which would have cost another $20 plus the cost of SSD which would have been another $60 for something along the lines of a 60gb drive.
Forgot to include monitor in the build, hopefully someone else can chim in on that I am not the most knowledgable in that area.