Best equipment for <=$1500 )(Max $1.800)

Hi, I want to upgrade my 3 years old HP Pentium D (2 GB RAM, 500 HDD, ATI AIW X1800XL 256 MB, SB X-Fi) and I want to get the most bang for my bucks ... I'm thinking in a Core 2 Quad CPU, 1 GB GForce 9800 Video Card (or similar), a good 5.1 sound and at least 1.5 TBs of disk ...

The use will be generic: Office and Internet surfing, some video/photo editing, some Multimedia Playback (HD) and recoding/encoding, some gaming, and lot of multimedia storage (>500 Gbs of photos, music and videos) ... of course, I want a reliable/solid performer for multiple tasks ... I've a 24" HP monitor and I want to have several window/apps opened and all of them working (better) without delays ... of course, I won't have 2 inntances of Crysis, plus 3 or 4 of a heavy compiling tasks, plus 2 Blue rays movies decoding ... just 'regular' tasks ... but want solid speed.

I 'think'/'believe' want minimun a Quad processor with 6 GB of RAM (I want 8 GB), and 1 GB Video card, but I'll study any suggestion for a solid performer candidate ... The only brand I'm seeing in this moment is HP, because offers me the broader choice of CPU/Memory/Disks, with the others I wasn't able to choose >4 GBs of RAM and looks as more limited systems ... but, of course, I'm open to onther brands, including a bare bone, or user built systems ...

Some additional info: I want a good sized/cooler [good ventilated] Deskop Case, no need for a fancy/lighted/good looking cases; No need for a lot of additional slots (Yes, I need Multimedia Card Reader and at least 4 USB ports); I'm not able to choose component by component and build it (I'm aware of compatibility chores... so I rather prefer a pre-built systems) ... also the price of $1.800 DO NOT INCLUDE the monitor, I've a HP 24" monitor that's enough for my needs ...

Thanks in advance,
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