Well, since you router only provide -b, you only need a -b card.
Netgear is a nice match but does not have to ... any Linksys, Dlink, Belkin, Motorolar ... should work fine !
If you plan to get a -g or better router later (mean soon) then go ahead and grab a -g pci card. Otherwise, don't waste your money ...
Check BB, CC, Staples, CUSA, Fry's ... look like they have it onsale for @10 bucks every other weeks.