What do you recommend?

Vista 32 Bit - 2GB DRR2 1066 Ram

or

Vista 64 Bit - 4Gb DRR2 800 Ram

this would be mainly used for gaming, would the 64 bit and 4gb make that much of a difference??? thanks

Whichever of the two has as lower CAS latency, and whether its 2 sticks in dual channel or one big stick isprobably more important than those factors.

what's more important? ddr2 XXXX or CAS latencysiskokidd

Depends.

Once you get up to DDR2 800, CAS is more important. I can gaurantee you that DDR2 800 with a CAS of 4 or 3 will outperform DDR3 1600 with a CAS of 9.