That systems looks good all of it. The only thing I might consider doing differently is going with a 6 core AMD build for gaming, but that said the 920 is a heck of a chip.
You might want to check some benchmarks to see where each CPU rates, pick the one with more power as the pricing is going to very much the same.
I originally started out with an AMD Phenom II X6 1090T Black Edition Thuban 3.2GHz 6 x and from what I've read it's almost a matter of preference. Someone correct me if I'm wrong, but from what I've read the AMD performs slightly better on things that take more threads, while the Intel ramps up a little better running fewer cores.
On the topic of CPU, should I buy a better cooler if I'm going to be overclocking? It comes with the stock fan and I don't think I'll be doing TOO much overclocking, but I guess it'd be nice to have the option.
Was just perusing the forums while stuff compiles, so I don't have time to do a full answer, but I figure I can at least point you in some better directions.
First, most people seem to agree that the price difference between the 920 and the 930 in negligible, so go with the i7 930
The mobo you picked is fine, but most people tend to stay away from OCZ memory.
Personally I would go with a spinpoint f3 or seagate 7200.12 (either 500gb or 1tb) instead because they are generally faster and cheaper.
IMO go with Antec or CoolerMaster for the case.
PSU is fine, actually some will consider overkill.
DVD burners do not need to be great, so maybe go with a cheaper LITEON, or find one with free shipping.
Thermal paste comes with stock cooler, or even most aftermarket coolers.
If this build is really just for gaming you can downgrade the CPU (and in turn the mobo and memory) with little to no change in performance and either save some money, or spend it on a fancier video card. Or use that money to get a good monitor.
Spending a little bit of time on newegg will probably gain you some combo deals to lower the price by a decent amount, probably enough to cover tax/shipping.
Also, you can get a CM hyper 212+ from amazon for ~$30 which will be plenty good for your overclocking needs.
With AMD and Intel, your understanding is correct. Personally, multi thread apps and games is what takes preference for me, so I'd probably go with the AMD. I have a friend with the 920 that's clocked the snot out of it, so it's a good option to. Either CPU is going to eat through anything with ease.
Your PSU should be fine unless you want to go crossfire. I'd maybe look at a 1000 in that case, then you have some room to move in case you want to add another hard drive or something else in the future.
Even with 5870 in crossfire he'll be fine with that 750 Corsair PSU.
And for the most part, games are not very multi-threaded for the CPU, there's even a Tom's article saying that 3 cores is really the sweet spot for current games.
6 cores actually reduces the efficiency of game playing.
At that price point, you will get better gaming performance out of an i5-750 or a Phenom II X4 955. The i5 will save about $150-200 over the i7 build, and the AMD build can save up to another $75-100, all of which could be spent on getting a 5870 instead of a 5850.
Technically, it's not the having 6 cores that reduces the gaming performance. It's that the value isn't there. The $200 1055T X6 has a lower clock speed than the 955/965. The $300 1090T X6 is the same speed as the 955, and offers no improvement in gaming. When you can pick up the 955 for $160, there's not much point to spend $40 more for worse performance or $140 more for the same performance.
Makes sense... What happened was I looked at the initial game benchmarks of the 1090T and the comparison with a 4 core phenom II with a number like 9 something something, and just assumed it was the similarly clocked 955, but of course it turned out to be the 965.