http://www.overclockers.co.uk/showproduct.php?prodid=MY-290-CS&groupid=701&catid=8&subcat=1517 - Memory - No silly heatsinks and is cheaper. There is no difference that you'll notice between the vengence and these.
http://www.overclockers.co.uk/showproduct.php?prodid=BU-036-OP&groupid=701&catid=5&subcat=1906 - P67 Motherboard - Comes with a CPU cooler (Since you chose the OEM 2500k) and a FREAKIN' GRENADE!...okay that part isn't really worth noting but the board is quality.
Can I ask, are you planning on using the features the Z68 give you?
The one that comes with the motherboard I posted is a reasonable cooler, definately at the speeds you've stated you'll be running. It comes with 4 SATA-III ports and you should be able to fit a PCI card in between two dual slot cards in Crossfire.
As for future proofing, you won't really need to upgrade just the CPU until you decide to upgrade your PC completely (New mobo etc) as Sandybridge chip such as the 2500k are very good chips and will be for the foreseeable future i.e 2-3 years.