Wich is better?

Hello,i'm new here and i was wondering,could someone tell me wich of the next laptops are better at runing games:
1. Acer Extensa 5630G
-Intel Core2Duo T5800 2.00GHz
-ATI Radeon HD 3650 512M-GDDR2
-RAM 2GB DDRII 667 MHz
-HDD 250GB SATA
-VistaHomePremium

or

2. ASUS PRO55SR
-Core2 Duo T5750 2.00GHz
-ATI Mobility Radeon HD3470 512MB VRAM
-2G DDRII667 RAM
-250G SATA HDD

I can't decide who will be the "winner",i've seen many videos of games that can run on these 2 laptops,but still,can't make up my mind,i was looking for games like Call of Duty 4,Bioshock,Gears of War,GTA IV and such.
Please help me

I must say that you gave me a verry good info,but teh thing is at the moment i'm on a laptop from Asus wich is Asus F5R series,and i was the "lucky" winner to get the damaged laptop(keeps freezing every now and then for about 5-10 sec,the temperature goes up up up...have to use a special cooling fan for laptops) but i was checking youtube and i must say that either ATI 3650 or HD 3470 are good,but maybe i'll try and search for HP,Dell or again Asus because thats a good info you gave me.But...why Acer laptops are like you saied? ^_^

and acer uses very generic parts, so u can't really do actual stuff without it malfunctioning, because most of their parts are very cheap and absolute crap.