Not looking for super duper high end stuff, yet you list a 280 and 1100w psu?
K, well for starters go quad preferably a Penryn 45nm Intel one such as the Q9550.
Ever plan on going sli? if yes, go EVGA 790i if not, i'd go with Asus P5K3 LGA 775 P35
i'd go with a P35 chipset as its tried and true. OR you can go with a DFI X38/X48 chipset, you do the research on what you need.
Ram, pretty much stick to the "brand" names and go with the one with the better warranty. OCZ Plat. 2x2GB DDR3 @ 1333mhz comes to mind.
PSU, Tagan, Toughpower, PC Power and Cooling if you got the cash, or an Enermax Galaxy.
Make sure you choose one with an 6+2Pin PCI-Express connector
Vista Ult. 64 bit hands down, that's not up for discussion if you plan on gaming.