The gtx 460 will work, you have a pci-e x16 slot, don't know if it is 1.0 or 2.0 but that makes no difference, the gtx460 2.0 will work even if it is a 1.0 mobo.
Thing is ; is your powersupply up to it ? You need a 500W psu with two 6 pin pcie cables.
You need at least one casefan, but more is obviously better.
Also take in account that the 460 takes the space of two slots because of it's casing and fan, so the small slot beneath the pcie slot has to be free.