what are you going to use it for? If you dont need to go too far, 802.11g will work fine for you. The wireless card doesnt determine the range that you will get, its the AP that does. so if you want a super long range, then get a signal booster for the router.
A good wireless card can hold the signal better, I have 2 belkin cards 1 is your standard 802.11g which always disconnects and has an aeriel doesn't seem to help it.
My new one is a belkin pre-N wireless card so 802.11n and has never lost its connection to my router it also doesnt use an aerial and works wonders.