I bought a Dell laptop last December, on the recommendations from friends, one of the main reasons being the warranty that they have.
Our model is the inspiron 1720.
It has Vista on it, but I think you can get whichever op system you want.
They are also good, in that you can call them tell them what you want, and they will e-mail you a quote which gives you a breakdown of all of costs of the different components that you want on your system.
My brother in-law also gets laptops there for my nieces who are also in University., and has been pleased with the service.