You definatly won't need SLi with a 19" screen and by the time you do need it for the price you will pay for the second card you will get less performance then for a single new card (89xx series or better by then).
Also I suggest you get a 22" widescreen with either the 320mb 8800GTS or the 640mb if you can afford it. I think all over it gives a better gaming expirence as you see more of the game

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You don't need a sound card as onboard is fine unless you are using $2000+ speakers and are a audiophile

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Also for the burner get SATA not IDE as SATA is the new they thing and you don't want that ugly IDE ribbon running through your beautiful new case

RAM wise you would be fine with 2x1GB of A-DATA 667MHz stuff. it's only $111.99 and you will notice a loss of 3fps max with IMHO isn't worth the $60 or so.
And I think that motherboard is overkill you could get away with a Gigabyte GA-965P-DS3 for half the price, ask yourself what has the ASUS got that the Gigabyte hasn't, then is it worth $100?
And finally for the much debated Power Supply. The PSU I would get isn't at
www.newegg.com (I'm from australia so I use a different shop) but it's called the Coolermaster iGreen 600W silent. If you could find that for a good price then get it as it will haddle your system fine and has a very good rep back here in Aus.
Anyway that's all I can be bothered changed ATM and sorry for the lack of links but I'm lazy
