definitely go with the conroe and you could also try it with the Gigabyte GA-965P-DQ6, supposedly in the reviews that board overclocks very well, i think i'd take it over the asus
Personally I'd go with the Intel D975XBX for that CPU. The major downside to that board would be the limited RAM voltage ajustments. Otherwise I'd go with the P5W-DH. Or the P5WDGS-WS PRO, but it might be a bit out of your price range...