The gateway looks the best, although I am now very confused about the graphics card. The bestbuy website lists it as 256 dedicated but
notebookcheck says it's integrated. Maybe it comes with 256 dedicated and can leech 256 from the system? Worth investigating.
Acer seems like the best out of the other 3. I'm not sure if asus' processor is better, since it is dual core but with only a quarter the fsb (unsure of the effect of fsb frequency). Asus also has ddr3 memory. According to
this site, ddr3 potentially runs at 2x the speed of ddr2 and uses less power.