I will go with dual core, as the difference in performance now is not alot, and it will greatly help when games go multi threaded, and single cores will not work well.
If you are overclocking, get the platinum series, if not, the generic ram will be fine.
Consider getting the Tsunami instead, as it is made better, and has vents in the front for air to get in, unlike the soprano, that has cheap plastic on the front, and no air vents.
Glad to see you know the truth of SLI.
Consider the A8N-SLI though, as the E looks crap. Also, get cable tidy kit, rounded IDE cable and UV reactive sata cable, along with a cold cathode.
Cisco CCNA, Comptia A+, 1/3 through CCNP