For $2000 I can quickly match you with the best bang for the buck off newegg.
If this is going to be an absolute gaming machine I would not go with a 200gig HD. For the best game rig setup go with 2 Raptors in raid 0 or just standalone having 2 raptors, one for all your online games and the other for all your PC games that are not online. Thats what I do and it works really well, raid doesn't give much more performance as some may think with 2 raptors so I just keep that simple and get 2 raptors stand alone.
Question, do you plan to overclock the system? If so you can save alot of $$$ and build the following system.
CPU-AMD 64 3200 Venice core 939>
$159 newegg.
AMD 64 3200 Venice
Motherboard-DFI LANPARTY nF4 SLI-DR Socket 939 SLI>
$186.99
Video Card-eVGA 7900gt 256mb superclocked PCI Express>
$369.00
Memory-OCZ EL Platinum Revision 2 1GB (2 x 512MB) 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) Dual Channel Kit>
$166.44
Hard Drive- x2 Western Digital Raptor WD740GD 74GB 10,000 RPM 8MB Cache Serial ATA150 Hard Drive>
$160.00 and has a $30 mail in rebate final cost $130 x2=
$260
DVD,cd Burner-NEC Silver 16X DVD+R 8X DVD+RW 8X DVD+R DL 16X DVD-R 6X DVD-RW 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2M Cache IDE DVD Burner>
$35.99
Case-Aspire X-plorer>
$58.00
PSU- Personal Preference but get a high end best quality for PSU 550 watt minimum and at least 38amps on 12v rail if single rail.
Sound Card-Creative Sound Blaster X-Fi XtremeMusic>
$121.99
Mouse-Logitech MX518
$33.89
Keyboard-Saitek PZ30AU Black 104 Normal Keys 4 Function Keys USB Wired Standard Eclipse Keyboard>
$46.95
Monitor if needed-NEC 19'' CRT, CRT is best for gaming.>
$179.99
Speakers-Logitech X-530 70 Watts 5.1 Speaker>
$58.99 These rock!!!
CPU cooling- Personal preference here again, heavy OCing on air with venice isn't a problem since Venice can OC really high with fewer volts then the cores before it. Venice 3200 939 @2.8 ghz on air with only 1.48v rock stable 24/7! Less volts less heat.
TOTAL= $1675 with 2 raptors and non SLI! Great deal huh, add in another $100 for S&H.
Now anything left out is whatever personal things you might add but that system above using the DFI board and a 3200 Venice core will OC like crazy, my brothers got the same system I built him a week ago except without the 7900gt, hes got it at 2.8ghz rock stable from 2.0 default speed. Like I said that system above is an awesome system for gaming if you OC, if not just exchange the CPU with a AMD 64 4000 San Diego core and leave it alone. That memory is also awesome, I been using it for over 1yr on my old system and on my brothers new comp, low low timing achieved with high OC, id have to get the actuall CPUZ info on the memory timings but I do know it was at 1t rate around 2.5 3 3 7 with the CPU 2.8ghz, id have to double check to get back to ya.
Anyway that system will do you alot of good and the newer 7900gt using the 90nm fab really is great to because less power consumption and heat and higher OC. Also that 7900gt is just as fast or just around same speeds as the 7800 GTX which cost almost $200 more! Anything else you need to know or on this build let me know, I wasn't sure if you wanted to OC or what and decided this is the best system high end for you, its not SLI because you wont need to with that new 7900gt because it performes so GODLY single GPU and going SLI on anything with these high end cards today is a waste of money because we can't tell on screen more then about 50 fps the human eye or so, and besides nothing really gets below like 68 fps with all the eye candy up on the heavy games of today on this new card.