Buying a laptop, What do you suggest?

So one of my christmas gifts is a laptop. I want to stay under $700 but I want it to be a good laptop for the $$. It needs to have a built in wireless card and the ram needs to be expandable up to 1g. Im going to be using it for mostly school work and internet but I also want to run all of my music off of it. Let me know what you suggest.

dell

warranty > *

and if you arent playing any games or anything like that:

dell

i love my HP

Im lookin at HPs mostly because they are cheaper. What type of processor do you prefer? The one Im looking into has anMobile AMD Sempron Processor 2800+ with AMD PowerNow Technology @ 1.6GHz. How is this comperaple to an Intel?