Personally, if you are looking at the FX-53 vs. 4000+, i'd go with the 4000+ San Diego at half the cost. The overclockablility will bring you to FX 53 performance and higher. OR if your willing to spend over $500 on a CPU, consider the X2 4400+, which with the right RAM, MOBO & PSU, you'll be able to OC to the 4800+ speeds and performance.
That Lian-Li case is really sweet, but there are many cases that are just as nice if not better for much less money. WD is a good HDD, but consider going Seagate for a SATA HDD. They are about $100.00 for 250GB. Seagate is one of the most trust HDD's on the market. 3 of my 4 HDD's are Seagates. They have the best Customer support as well as several great free downloadable HDD utilities.
With all of this money you'd save from my recommendations, you could buy the 7800GTX instead of the GT. You could even probably upgrade to the 7800GTX 512MB. woot!