System Usage from Most to Least Important: Gaming, Video Editing, Photoshop
Parts Not Required: Keyboard, Windows 7 Ultimate
Preferred Website(s) for Parts: Any
Parts Preferences: No preference.
SLI or Crossfire: Unsure what this means, sorry.
Monitor Resolution: 1920x1080
Additional Comments: I'd like something that'd last me at least 4 years and a 24" monitor equipped for predominantly gaming, not for photo/video editing (though that is important). I was thinking that perhaps teaming the ASUS MLH248H monitor with these speakers would be a good option. I'm also interested in having a small 64-128gb SSD drive in conjunction with an HDD in order to get faster boot times and better performance with programs like Premier and After Effects.
That's all I can think of for now, thanks in advance guys!
SLI/Crossfire -> Means using two or more graphics card together to get more performance.
Scalability of this system could go from 0% (game not optimized for this tech) to 100% (perfect scaling).
Usually it's pricier to get a better card than two smaller cards together that equals in performance to the big one.
But you do have more noise, more heat, and usually some stuttering problems (some people mistake this for lags).
If you have the money, stick with one bigger card solution
SLI: As Vitornob mentioned, it's about using multiple graphics cards at once. You have to use the exact same GPU. That is, a GTX 570 with another GTX 570 or a Radeon 6970 with another 6970. Brands, frequency, memory etc. don't matter, but the Graphics Processor (GPU) has to be the same.
Personally, I wouldn't recommend it straight out the box, but at a later date, with more GPU intensive games out in 'bout a couple of years time, you may consider it, but not now if you ask me.
SSD: $199 Corsair Force Series 3 120GB - 64GB SSD's are mostly pointless these days. Win7 itself takes up almost 40 with all the updates, service packs, logs, page files, hibernate files etc. And Ultimate as you've mentioned is just bigger than the Home Premium (say). And Win 8 ain't gonna be any smaller
Total: $1254 Plus Shipping. (Maybe you should not get the mechanical HDD now if you want to keep your expenditure under check - unless you're a total media junkie and need a helluva lot of storage right out the box - $1155 without it )
P.S: If you're serious 'bout editing etc. (Professional level), starting off with 16GB RAM won't hurt.