You picked a really good processor. They aren't available in most stores yet, but should be soon. That E6600 will be much faster than the Athlon 64 I had last year. Socket 775 is the same as LGA 775 like you suspected. Socket 775 is a
Land
Grid
Array based socket, which is where LGA 775 comes from. It's also known as Socket T.
HSF: Doesn't much matter since you don't plan to overclock. If you are getting the retail version of the E6600, it'll come with an Intel-approved heatsink and fan.
As for memory, it wouldn't hurt to spring for 2GB. Vista is going to be a real resource hog and some games can eat up a gigabyte by themselves. Any real image or video work will also eat up a lot of memory. Some high performance Corsair memory would provide good reliability and fast timings. Newegg happens to be running a special on it right now, actually:
http://www.newegg.com/Product/Product.a ... 6820145590 for $220 (take $40 off that if you send in a rebate, too).
Graphics performance is the expensive part. You'll do well to get either an nVidia GeForce 7900GT or 7900GTX, depending on how deep your pockets are. Both of these cards are PCI-E, which isn't a big deal since almost any motherboard you buy will support PCI-E these days. I had to do some fancy research just to get my hands on that AGP X800XTPE last fall. The 7900GTs run about $270 (
http://www.newegg.com/Product/Product.a ... 6814127218) or you can get a 7900GTX for about $450 (
http://www.newegg.com/Product/Product.a ... 6814130037). Either one should be very fast and suit your needs. Don't buy into the SLI/Crossfire crap floating around on the Internet. One card is plenty. The performance difference in real world game performance between a single card and an SLI setup is often under 40% higher. Additionally, by the time a single high-end card gets slow enough to consider an upgrade, there will be features you'll want not available on older generation hardware (such as DirectX 10 support). Having two cards just wastes money.
As for your motherboard, you'll definately want something with an Intel 965 chipset. The older 975 based boards sometimes say they support the new Core 2 Duo processors, but it's more of a hack job than anything. For best performance and reliability, the 965 is desirable since it was made specifically for the Core 2 Duo processors from the beginning. A good ASUS board might do the trick at about $160 (
http://www.newegg.com/Product/Product.a ... 6813131030).
For your monitor, I'd really prefer to see you go with a 20.1" LCD instead. Most 19" LCDs run 1280x1024, which is not a true 4:3 resolution (1280x960 is instead). However, a lot of 20.1" LCDs run 1600x1200, which is a true 4:3. If you prefer a 19" due to money reasons, however, I'd suggest one of Dell's panels. Try to get an 8ms panel. Panels that claim to be faster than that are almost always TN based panels which cannot reproduce color as well as other technologies. They also have a poor viewing angle. MVA based panels that employ overdrive technologies commonly are marketed as 8ms. IPS panels are also good and fall under 8-12ms. Try not to get a 16ms or slower panel. If you want more specific advise, let me know. Expect to pay about $200-250 for a good 19" LCD or $450-500 for a good 20.1" LCD.
Hard drives are an easy suggestion.
If you want a wireless mouse, get a G7. If you want a wired mouse, I'd suggest a G5. Try to stay away from the MX1000--it's got a power saving lag that's hell for games. (The newer 1000s don't have this problem quite so bad).
I wouldn't trust onboard sound if you want something that sounds good and lasts long. Turtle Beach makes some good midrange cards with excellent sound. For example, the Montego ($67) is a really high quality card that supports all the major 3D sound technologies such as EAX and OpenAL.
http://www.zipzoomfly.com/jsp/ProductDe ... ode=361102 It's probably overkill, but if you can afford it I'd suggest this model. They do have cheaper ones though.
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This thread had no replies when I started my reply. Heh.
Also, don't expect much in the way of good computer advice off of this forum. (Sorry folks, but a lot of people here don't know malarkey about computers. You know who you are. The Internet isn't a big dump truck, nor is it a series of tubes...)