i3, but instead of a 2320, I'd just get a 2100. And the HDD space all depends on how much stuff you want to store.

if i only had the two options i would go with the i5 but instead of the 1tb hdd i would go with a 60gb ssd for the os and a 500gb for storage and in the future if you need more gpu power just throw another 550 ti on there and sli it up with the i3 future upgrades will be annoying and really there is not much more gpu power you can do without a cpu upgrade as well

Burrow's got it. An i3 2120 is just extra MHz, so just get the i3 2100 and the 660 ti. Here are some links, but definitely go with the Galaxy 660 ti because it has the lowest temps and I own one and love it!
Extra VRAM is never hurtful, there are lower VRAM cards for $40 less, I think it's worth it for multi monitor support.
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Get this motherboard with the i3
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As far as HDDs, you don't need an SSD for boot, but its helpful for big enthusiasts. You can get away with a high rpm hard drive for boot and storage. I prefer and recommend (from personal experience) the WD Caviar Black. It comes in 500GB, 750GB, 1TB etc. I recommend people get 1tb because mechanical hard dives tend to slow down in performance after they fill up over half way. Though it's all up to you.