I am still a noob and I need to have a computer to watch DVD/Blu-Ray/HDTV in my bedroom. I have a nice looking monitor but my PC is just an old fart. Please build it from hardware to software, so I'll probably just buy everything you've suggested off from newegg.com. Thanks.
Total: $687 + S&H (not counting MIR, specials/combo deals)
This is just to be equal to the AMD system listed (with a better case of course) The reason the AMD system has no video card is it has a good one integrated into it, so it uses less power, runs cooler, and can still play whatever BRD you throw at it (taking PowerDVD into account).
There is no reason to go with a 32-bit OS on a new build. Especially not Vista Basic. This is for a HTPC so you'll definitely want Vista Home Premium for the built-in Media Center functionality. IH8U's build has pretty low-quality components (so-so PSU, motherboard, and HD) and comes in almost $200 over budget.
Is there any reason you're stuck on an Intel build? Like P00p00head said, AMD is actually a better choice for a HTPC. The integrated GPU in my build above is more than enough for 1080p Blu-Ray playback. There is no reason for a separate GPU. I would really try to ditch your Intel bias. Do some research and you'll see that most HTPC's use an AMD platform.