The 7870 is a $300 card versus the GTX 650 Ti which is around $160. You can't really compare them but the 7870 pretty much blows it out of the water. That said, the i5 will generally perform a bit better but there are better AMD chips, namely the new Vishera processors.
The 8320 will be better than the 8120 and is more level with the i5. The new AMD processors are better than the old ones in every way and there's no reason to get the old ones now. On average, they're at least 10%-15% faster than Bulldozer processors.
In general the graphics card is more important for gaming but there are games that need a strong CPU as well, Skyrim being one of them. I would probably opt for the one with the better GPU, but you should seriously not bother with the 8100s and get an 8320 or 8350. IBuyPower does offer them.
The difference between them is that the 8350 is clocked at 4GHz and the 8320 is 3.5GHz.
Ill start by saying im an intel fan, but for the money and the options you provided, id go the AMD route, that GPU should handle just about anything, the only bad part about the 8120 is that most games arent optimized for 8 cores, let alone AMD cpus. Oh and stick with 2x 4gb sticks, it leaves room for upgrading to 16gb later.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.