For cpu hsf, look at Thermaltake Big Typhoon, Scythe Infinity, Thermalright SI-128, or the Noctua nh-u12. If you really want to replace the case, which you probably don't need to, look at the Silverstone TJ-06. Also get some Yate loon 120mm fans to replace the ones that came with the case you have, and to use on the cpu hsf, and get a fan controller to speed them up, they push alot of air at 1400rpm.
C2D E6600 @ 3.15ghz w/ 1.35 vcore
2GB G.Skill DDR2-800 (4-4-4-12)
XFX 7600GT xXx