Best mobo, CPU and VGA combination?

Hi,

1) What would be the best combination of my available parts to make my computer "DS2" as good/fast as possible?


I have these parts:

Intel E2180 @2.0 GHz
Intel E5400 @2.7 GHz
Intel E7500 @2.93 GHz

Asus P5KPL-CM; DDR2 4Gb 800 [400Mhz]
Gigabyte EP41-UD3L; DDR2 4Gb 800 [400MHz]
Asus P5P41T LE; DDR3 8Gb 1333 [667MHz]

Nvidia GeForce 210; 512Mb
Nvidia GeForce 7300 LE; 128Mb
Nvidia GeForce 9400 GT; 1Gb
Nvidia GeForce 9800 GT; ?
Nvidia GeForce GT630; 1Gb

HDD 1T SATA-600 32Mb 7200 [WDC WD10EALX-009BA0]
HDD 1T SATA-600 64Mb 7200 [ST1000DM003-9YN162]


I need the best setup for DS2, then the 2nd best for DS3 while I just need DS5 to be good enough to search the Net.

Thanks,
Andy


PS My computers are currently:

DS2
===
Intel E7500 @2.93 GHz
Gigabyte EP41-UD3L; SATA-300
DDR2 4Gb 800 [400MHz]
Nvidia GeForce 7300 LE; 128Mb
C: 320Gb SATA-300 7200 16Mb 7200 8.5ms [Hitachi HDP725032GLA360]


DS3
===
Intel E5400 @2.7 GHz
Asus P5P41T LE; SATA-300
DDR3 2Gb 1333 [667MHz]
Nvidia GeForce 210; 512Mb
C: 250Gb SATA-300 8Mb 7200 8.5ms [Hitachi HDT725025VLA380]


DS5
===
Intel E2180 @2.0 GHz
Asus P5KPL-CM; SATA-300
DDR2 4Gb 800 [400Mhz]
Nvidia GeForce 9400 GT; 1Gb
C: 160Gb SATA 8Mb 7200 11ms [MAXTOR STM3250620A]