Purely FWIW... maybe just a LOT of trivia?...
You **might** want to check out the quads instead -- several are pretty cheap, although not as cheap as dual core obviously... the reason I say that is because of the video encoding. Another issue to consider is the MOSFETs, usually between the CPU socket & the m/board outputs -- I don't know about, haven't researched these newer boards, but in the earlier versions a LOT of manufacturers skimped on the part specs they used, so they'ld overheat trying to supply voltage to the CPU that they were only marginally capable of... I had 2 different brand boards burn up [one literally] under warranty because of that -- for the board I'm using now I paid extra for a model with a heatsink over those MOSFETs & haven't had problems [knock wood].
I'd also suggest more RAM for win 7, though I'm not familiar with the prices & availability where you live -- in the US NewEgg & others will sell you 6-8 GB for less than you've listed [often Much less]. Personally I haven't seen a benefit to trying to buy faster/better RAM with the AMDs -- running 4 or more GB using 4 sticks was a weak point I hope they've fixed, because setting the timings was a PITA... had to put everything to auto, boot/post, then start tweaking from there, but it was a pain on the 5 I've built. Also research to see what voltage folks use with that m/board chipset & the brand/model of RAM you buy -- Lower is better, some manufacturers list max rather than preferred voltage, some m/board Bios are off [voltage stated is not voltage supplied], & long story short, be prepared to increase it if the new system doesn't run stable, & being prepared includes making sure the m/board bios lets you.
Whichever AMD CPU you wind up getting, please note that they Do Not like heat... they have a pretty low threshold & when it gets close to that they'll often start throwing errors that slow things down. AMD's Black Edition CPUs are made to overclock, but at some point you have to up the voltage to keep the system stable. Upping the voltage increases how hot they get. Think about getting a 3rd party CPU heatsink/cooler rather than relying on anything OEM. Also research what others run in the way of case fans etc. for that Antec case. If it helps picking out a heatsink/cooler setup, watch out for heatsinks that are too large for your case [check dimensions] &/or too heavy for the m/board [some are]. Also watch out for sharpness -- some of the Zalman's for instance could slice off a finger. I usually keep it about 80 degrees Fahrenheit here in the summer [I'm not very temperature tolerant], so always worried about, kept an eye on CPU temps -- this year I splurged on a H70 water cooler, & it was wonderful to not to have to worry about that, but then cleaning out the case I found signs of seepage & it's off being RMA'd right now.
RE: the DVD burner -- check out ratings etc. @ club.myce.com... they have a wealth of info. And while you're there check out MediaCodeSpeedEdit, make sure the drive's supported, & use it while the drive's new enough to return/exchange on the somewhat rare chance something goes wrong. Basically DVD drives usually have a sort of built-in speed governor as a means of DRM -- it won't stop users from copying, but makes it more time consuming. MediaCodeSpeedEdit will let you remove that. As far as Nero Essentials goes, it's cool, but do not pay more than the equivalent of a couple dollars for it in the price. As far as the hard drive goes, don't be fooled by the SATA III/6Gb/s rating/spec... it's nice to have as a means of future proofing, but most hard drives can't reach the transfer speeds to use it -- you'd need one of the solid state drives to actually put SATA III to use. IOW for two drives priced the same, get the one that's SATA III, but don't pay extra for it. Do research the exact model you want to buy though -- Seagate has produced some real dogs, & Western Digital has made some really trouble-prone drives as well. Also research the warranty -- some hard drives come with a 1 year warranty starting with the date of manufacture, which may be almost expired when you buy it.
Power supplies are a *Really* complicated subject. Specs etc are very often at least partially lies, heatsinks are often made of scrap metal, counterfeit parts are common -- I've even seen pictures of capacitors stuck inside larger casings with false branding/specs -- and a surprisingly large number of power supplies do not have any safety certification [like the UL listing in the US]. And when they do show certification, that can be for a similar design rather than the one in the box! Selling power supplies is lucrative, so a very large number of companies put their brand on various products they neither design nor manufacture -- for most brands there are a relative few good models, & several that are total junk. When shopping for power supplies a general rule of thumb is if you don't do anything else, compare weights -- a cheaper POS will be much lighter, though unfortunately you'll soon find that's the majority of cheaper units. You can also look for brands that are known for power supplies rather than every sort of product, though again that's no guarantee you won't buy one of their bad products -- best bet is to try & find a detailed review where someone's actually taken it apart & measured every aspect of performance.
That all said, in your case you do not need a 850 watt power supply. There are several web sites that have calculators where you plug in your expected hardware & get the wattage number needed. The biggest consumer of power will likely be a higher end graphics card, & AFAIK the only reason for going to 850 watts is if you want to run 2 of them. If you do want to pick up an Nvidia card, I think there might be some fermi 460 1 GB cards left going at closeout pricing, which might be the best value in terms of performance for price. For ATI the best deals I've seen recently are for the 6870 at around $150 US after MIR. Both are a lot of graphics card for the money, & both offer hardware acceleration for video display/encoding. Bear in mind that these sorts of graphics cards also take up two slots worth of room, so you'll loose the use of whatever slot is directly below them.
[BTW, rather than always buying canned air, we bought a very small, cheap air compressor, & I fitted the blow-gun attachment with the same sort of tube or straw the canned air comes with. It's saved us a fortune & is I think much more environmentally friendly if that matters to you. It's also great for dusting. :-) Another thing I do is on the cases that allow it, I use the pre-filter material used with various air purifiers. It's a black, fibrous sort of material that can be easily cut & held in place with the rough half of velcro tape or tabs. Another thing I found going to a black case, sitting under the desk it can sometimes be a chore to find the buttons for the optical drives etc... I wish I had known that starting out because I would have integrated some sort of lighting when I put it together (there are all sorts of lights just for that situation, often used with or for music gear on stage)]
