Get the e78 imo. The classified is a waste of money if you aren't going to be doing some heavy overclocking. The e760 and e758 are mostly overclocking boards, there isn't much point in buying them if you aren't going to do that. It's why they're more expensive, better capacitors, better voltage regulation. I'd suggest getting an asus, Newegg.com - ASUS P6X58D Premium LGA 1366 Intel X58 SATA 6Gb/s USB 3.0 ATX Intel Motherboard - Intel Motherboards
as its got SATA 6gbs and USB 3.0. It also should handle lower level overclocking quite well.
Also don't get a XXX version card, just buy the normal one, save some cash, and overclock it. I'd also suggest getting the 640gb WD blacks, as the 750 are dual platter (AFIAK, don't quote me) which might be a bit slower.
Also have you built a pc before? Water cooling is very expensive and can potentially cause a lot of harm if you don't know what your doing. Going with air is cheaper and almost as good now with a nice heatsink, TRUE copper or the megahalems seem to be popular now. Or there's the core contact, cheap and works great.