Dual core, no clue

[BenjaminJoffe]

Hey,
I'm trying to get my PCs to run SB on both cores, from the forums I read that I should run 'two copies', I don't really get what that means, so I just opened the same client twice, turned out they just doing the same tests, no apparent extra benefits.
So I installed a second version of SB, now both installations were doing the same test again, but a brand new one so 2 weeks of calculations were lost.
After uninstalling the 2nd installation the work is still lost (lost for good?).
I'm no computer freak, and don't understand *why* I should have to hunt around to figure this out.
So please tell me, as a stupid windows user what I should do, any response along the lines of: "execute -r 4390:something" should ideally explain how the heck I run a command
Sorry for my ignorance on this.
Cheers,
Ben.

Edit, yes from this tutorial I cann see that the test is truly gone.
PS. I'm not a complete computer illiterate, in fact I've worked as a JavaScript programmer for two years now, but I feel that this whole system should be more user friendly for people not familiar with regular compiled apps.