Which Laptops/Notebooks are ideal for college?

I'll be going to Mcgill this fall and I need a laptop that has very good battery life, is light with at most a 15 inch wide screen. I also need it to have atleast a 1GB video Card, bluetooth(optional), atleast 4GB RAM, 2.5 Ghz or more processor with Turbo Boost(or equivalent) to above 3 Ghz. More than 250ROM as well. the company can be Dell, Toshiba, HP, Samsung etc.