If you've got an N router, you may as well get a wireless NIC that is 802.11N compatible as well. Since 802.11n has been ratified, i would avoid products that say 'draft' N on them, as they will be utilizing older versions of the standard.
In any case, N is the way to go short of running cables. Stick with linksys, dlink, trendnet, all pretty reliable brands. I've had bad luck with netgear.