EDIT: And, just in case, if you have any suggestions that can substantially improve my current build, don't be shy in suggesting them.
EDIT2: Also, the only reason I'm asking instead of just looking at a chart and saying "Hmm, this video card is better than my current one!" or something is because if left to my own devices I'd probably end up with pieces that aren't compatible with one another.
I have a bit of money I'd like to spend on improving my computer--running on all minimum graphics @ 30fps during raids and only occasionally (once every two weeks or so) crashing is *tolerable*, but why not enjoy the pretty colors?
I'm pretty weak in describing what I already have in my computer--what I do know is as follows (some information might not be worded the correct way, or maybe superfluous)
Windows 7 Ultimate Service Pack 1 (build 7601)
System Model:
ASUSTeK©
Main Circuit Board:
Board: ASUSTeK Computer INC. P5N7A-VM Rev 1.xx
Serial Number: MS1C8AB49002033
Bus Clock: 333 megahertz
BIOS: American Megatrends Inc. 0519 04/29/2010
Processor
3.15 gigahertz Intel Core2 Duo
64 kilobyte primary memory cache
6144 kilobyte secondary memory cache
64-bit ready
Multi-core (2 total)
Not hyper-threaded
Display
ATI Radeon HD 5670 [Display adapter]
Gateway HX2000 [Monitor] (19.9"vis, s/n C180C0114009, February 2010)
Controllers
Standard floppy disk controller
ATA Channel 0 [Controller] (2x)
ATA Channel 1 [Controller] (2x)
Standard Dual Channel PCI IDE Controller (2x)
Bus Adapters
Standard Enhanced PCI to USB Host Controller (2x)
Standard OpenHCD USB Host Controller (2x)
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What I want: I want a build that is capable of running World of Warcraft at full "Good" graphics at 40 fps+ in a 25-man raid setting, at 1920x1080 resolution. If a final build within my price range (below) can run better than that, I will certainly not complain! If I do not have to replace my entire build but rather just have to replace my graphics card or CPU, that would be great news too.
How much I am willing to spend: Somewhere between $200 and $1000. I would feel most confident below $600, but if you have a suggestion that reaches above that, don't hesitate to suggest it. Note that I need a new monitor to be able to run at 1920x1200. If that is a very expensive component and would degrade the other possible upgrades, I am fine with sticking with my current monitor (as, like my graphics card, it is relatively new).