I'm open to suggestions on all of these of course, I've got some experience replacing/upgrading parts, but this is my first bottom up build, so I'm looking for some help, and the community here is well known for offering just that!
I didn't see a processor in your list. The Raidmax 500s psu (newegg is down atm) is a no-no; more than 50% of the hardware problems resolved here are psu related. Use a Samsung Spinpoint 500GB instead of the WD - its cheaper and faster. Finally, the 5670 might work OK at 1680, but not sure it can handle WoW and a stretched desktop.
You are probably better off with an AMD build at this budget level - an i5 750 is going to run ~$800+ with a 5670, and IMO you should have at least a 5770 for what you are doing.
I'll put together a 750 build when Newegg comes back - someone else will do an AMD build I'm sure.
^+1 I think AMD will be a better fit for your budget, but budgets need a bit of flexibility.
Also, don't skimp on your power supply. If you go cheap you will be sorry. Get a quality unit you can trust.
If you really want nVidia, I'd say go for the GTX460. Otherwise the HD 5770 is a great mid range card.
Oops, too slow. Well I like this build directly above.
This is probably a more balanced build with some better quality components in the mix.
Went for a phenomII tri core with 6mb L3 cache @ 3ghz, Reason being by using core unlocker in the bios of the selected mobo you get a quad core @ 3ghz for $88
This build is complete with OS for $744.90 after MIB of about 25 bucks
You could gut another 30 or 40 bucks out of it by going for a cheaper case and psu but personally this build would serve you very well.
the 5830 isnt a good GPU for that price u may as well go down to a 5770 or a 4601gb or upgrade to the 5850
otherwise any of the listed AMD builds are good for your needs
Actually its a very good gpu for the price, if you have a look at newegg right now the gpu I specced in the above build is the same price as a 5770 after MIB hence the reason I put it in the build, it averages 5 to 10 frames more performance at 1680x1050 over a 5770 and 8-10 frames less than a far more expensive 5850.
Your comment may have been true when this card was around the 200 mark but its actually starting to hit a bit of a sweet spot.