The Asus G71 you linked from bestbuy is one of the best values out there. You are going to get near desktop performance for not a whole lot of money. I would recommend it over the G50 in the 2nd link for 3 reasons:
1) The faster GPU in the G71 will be great for Shooter games like Fallout 3
2) The Faster CPU will be good for your MMORPG's which tend to like a little bit more processing power
3) It's not a refurb. Not saying that there is anything wrong with the refurbished G51, but I personally would buy an expensive electronic product that was returned for some reason.