Help me choose a laptop for college - Engineering

[surftheiop]

Im going to Cornell next year and they have a deal through the school to get discounts on Dells and Macs.
As far as Dells you can configure any Optiplex, Latitude, Precision or PowerEdge to your specifications.

About what i want you use it for: Pretty much multipurpose, main thing ill use for is typing papers/doing research etc..
Im not a huge gamer but I definately would want the ability to play CS:Source and have enough graphics to run LOTRO or comparable MMORPGs (im not playing any now but have in the past and i would want to be able to play one if it really caught my eye). But i dont need a super top of the line gaming rig by any means. Also i dont want it to be like 10 pounds or something because that would just defeat the purpose of having a laptop. I dont really plan on watching movies on it or having a ton of music so hard drive isnt much of a priority.
I dont really have a set price range but i dont wanna buy the most expensive thing just for the sake of having the most expensive laptop.